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itemscope="" itemprop="itemListElement" itemtype="https://schema.org/ListItem" class="breadcrumbs__item"><a class="breadcrumbs__link" itemprop="item" href="/docs/next/how-to-landing/"><span itemprop="name">Tutorials</span></a><meta itemprop="position" content="1"></li><li itemscope="" itemprop="itemListElement" itemtype="https://schema.org/ListItem" class="breadcrumbs__item breadcrumbs__item--active"><span class="breadcrumbs__link" itemprop="name">Message retention and expiry</span><meta itemprop="position" content="2"></li></ul></nav><span class="theme-doc-version-badge badge badge--secondary">Version: Next</span><div class="tocCollapsible_ETCw theme-doc-toc-mobile tocMobile_ITEo"><button type="button" class="clean-btn tocCollapsibleButton_TO0P">On this page</button></div><div class="theme-doc-markdown markdown"><header><h1>Message retention and expiry</h1></header><p>Pulsar brokers are responsible for handling messages that pass through Pulsar, including <a href="/docs/next/concepts-architecture-overview/#persistent-storage">persistent storage</a> of messages. By default, for each topic, brokers only retain messages that are in at least one backlog. A backlog is a set of unacknowledged messages for a particular subscription. As a topic can have multiple subscriptions, a topic can have multiple backlogs.</p><p>As a consequence, no messages are retained (by default) on a topic that has not had any subscriptions created for it.</p><p>(Note that messages that are no longer being stored are not necessarily immediately deleted, and may still be accessible until the next ledger rollover. Because clients cannot predict when rollovers may happen, it is not wise to rely on a rollover not happening at an inconvenient point in time.)</p><p>In Pulsar, you can modify this behavior, with namespace granularity, in two ways:</p><ul><li>You can persistently store messages that are not within a backlog (because they've been acknowledged by every existing subscription, or because there are no subscriptions) by setting <a href="#retention-policies">retention policies</a>.</li><li>Messages that are not acknowledged within a specified timeframe can be automatically acknowledged, by specifying the <a href="#time-to-live-ttl">time to live</a> (TTL).</li></ul><p>Pulsar's <a href="/docs/next/admin-api-overview/">admin interface</a> enables you to manage both retention policies and TTL with namespace granularity (and thus within a specific tenant and either on a specific cluster or in the <a href="/docs/next/concepts-architecture-overview/#clusters"><code>global</code></a> cluster).</p><blockquote><h4 class="anchor anchorWithStickyNavbar_LWe7" id="retention-and-ttl-solve-two-different-problems">Retention and TTL solve two different problems<a href="#retention-and-ttl-solve-two-different-problems" class="hash-link" aria-label="Direct link to Retention and TTL solve two different problems" title="Direct link to Retention and TTL solve two different problems"></a></h4><ul><li>Message retention: Keep the data for at least X hours (even if acknowledged)</li><li>Time-to-live: Discard data after some time (by automatically acknowledging)</li></ul><p>Most applications will want to use at most one of these.</p></blockquote><h2 class="anchor anchorWithStickyNavbar_LWe7" id="retention-policies">Retention policies<a href="#retention-policies" class="hash-link" aria-label="Direct link to Retention policies" title="Direct link to Retention policies"></a></h2><p>By default, when a Pulsar message arrives at a broker, the message is stored until it has been acknowledged on all subscriptions, at which point it is marked for deletion. You can override this behavior and retain messages that have already been acknowledged on all subscriptions by setting a <em>retention policy</em> for all topics in a given namespace. Retention is based on both a <em>size limit</em> and a <em>time limit</em>.</p><p>The diagram below illustrates the concept of message retention. |
| <img loading="lazy" alt="Concept of message retention in Pulsar." src="/assets/images/retention-1dfff1bb477b98049ae06fcd16a51fda.svg" width="920" height="581" class="img_ev3q"></p><p>Retention policies are useful when you use the Reader interface. The Reader interface does not use acknowledgments, and messages do not exist within backlogs. It is required to configure retention for Reader-only use cases.</p><p>When you set a retention policy on topics in a namespace, you must set <strong>both</strong> a <em>size limit</em> (via <code>defaultRetentionSizeInMB</code>) and a <em>time limit</em> (via <code>defaultRetentionTimeInMinutes</code>) . You can refer to the following table to set retention policies in <code>pulsar-admin</code> and Java.</p><table><thead><tr><th>Time limit</th><th>Size limit</th><th>Message retention</th></tr></thead><tbody><tr><td>-1</td><td>-1</td><td>Infinite retention</td></tr><tr><td>-1</td><td>>0</td><td>Based on the size limit</td></tr><tr><td>>0</td><td>-1</td><td>Based on the time limit</td></tr><tr><td>0</td><td>0</td><td>Disable message retention, which means messages are not reserved (by default)</td></tr><tr><td>0</td><td>>0</td><td>Invalid</td></tr><tr><td>>0</td><td>0</td><td>Invalid</td></tr><tr><td>>0</td><td>>0</td><td>Acknowledged messages or messages with no active subscription will not be retained when either time or size reaches the limit.</td></tr></tbody></table><p>The retention settings apply to all messages on topics that do not have any subscriptions, or to messages that have been acknowledged by all subscriptions. The retention policy settings do not affect unacknowledged messages on topics with subscriptions. The unacknowledged messages are controlled by the backlog quota.</p><p>When a retention limit on a topic is exceeded, the oldest message is marked for deletion until the set of retained messages falls within the specified limits again.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="defaults">Defaults<a href="#defaults" class="hash-link" aria-label="Direct link to Defaults" title="Direct link to Defaults"></a></h3><p>You can set message retention at instance level with the following two parameters: <code>defaultRetentionTimeInMinutes</code> and <code>defaultRetentionSizeInMB</code>. By default, both parameters are set to <code>0</code>, which means disabling message retention.</p><p>For more information on the two parameters, refer to the <a href="/docs/next/reference-configuration/"><code>broker.conf</code></a> configuration file.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="set-retention-policy">Set retention policy<a href="#set-retention-policy" class="hash-link" aria-label="Direct link to Set retention policy" title="Direct link to Set retention policy"></a></h3><p>You can set a retention policy for a namespace by specifying the namespace, a size limit and a time limit in <code>pulsar-admin</code>, REST API and Java.</p><div class="tabs-container tabList__CuJ"><ul role="tablist" aria-orientation="horizontal" class="tabs"><li role="tab" tabindex="0" aria-selected="true" class="tabs__item tabItem_LNqP tabs__item--active">pulsar-admin</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">REST API</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">Java</li></ul><div class="margin-top--md"><div role="tabpanel" class="tabItem_Ymn6"><p>You can use the <a href="/reference/#/next/pulsar-admin/namespaces?id=set-retention" target="_blank" rel="noopener noreferrer"><code>set-retention</code></a> subcommand and specify a namespace, a size limit using the <code>-s</code>/<code>--size</code> flag, and a time limit using the <code>-t</code>/<code>--time</code> flag.</p><p>In the following example, the size limit is set to 10 GB and the time limit is set to 3 hours for each topic within the <code>my-tenant/my-ns</code> namespace.</p><ul><li>When the size of messages reaches 10 GB on a topic within 3 hours, the acknowledged messages will not be retained.</li><li>After 3 hours, even if the message size is less than 10 GB, the acknowledged messages will not be retained.</li></ul><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces set-retention my-tenant/my-ns </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--size 10G </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--time 3h</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>In the following example, the time is not limited and the size limit is set to 1 TB. The size limit determines the retention.</p><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces set-retention my-tenant/my-ns </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--size 1T </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--time -1</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>In the following example, the size is not limited and the time limit is set to 3 hours. The time limit determines the retention.</p><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces set-retention my-tenant/my-ns </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--size -1 </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--time 3h</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>To achieve infinite retention, set both values to <code>-1</code>.</p><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces set-retention my-tenant/my-ns </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--size -1 </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--time -1</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>To disable the retention policy, set both values to <code>0</code>.</p><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces set-retention my-tenant/my-ns </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--size </span><span class="token number">0</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--time </span><span class="token number">0</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><p><a href="https://pulsar.apache.org/admin-rest-api?version=3.2.2&apiversion=v2#operation/setRetention" target="_blank" rel="noopener noreferrer">POST /admin/v2/namespaces/:tenant/:namespace/retention/setRetention</a></p><div class="theme-admonition theme-admonition-note alert alert--secondary admonition_LlT9"><div class="admonitionHeading_tbUL"><span class="admonitionIcon_kALy"><svg viewBox="0 0 14 16"><path fill-rule="evenodd" d="M6.3 5.69a.942.942 0 0 1-.28-.7c0-.28.09-.52.28-.7.19-.18.42-.28.7-.28.28 0 .52.09.7.28.18.19.28.42.28.7 0 .28-.09.52-.28.7a1 1 0 0 1-.7.3c-.28 0-.52-.11-.7-.3zM8 7.99c-.02-.25-.11-.48-.31-.69-.2-.19-.42-.3-.69-.31H6c-.27.02-.48.13-.69.31-.2.2-.3.44-.31.69h1v3c.02.27.11.5.31.69.2.2.42.31.69.31h1c.27 0 .48-.11.69-.31.2-.19.3-.42.31-.69H8V7.98v.01zM7 2.3c-3.14 0-5.7 2.54-5.7 5.68 0 3.14 2.56 5.7 5.7 5.7s5.7-2.55 5.7-5.7c0-3.15-2.56-5.69-5.7-5.69v.01zM7 .98c3.86 0 7 3.14 7 7s-3.14 7-7 7-7-3.12-7-7 3.14-7 7-7z"></path></svg></span>note</div><div class="admonitionContent_S0QG"><p>To disable the retention policy, you need to set both the size and time limit to <code>0</code>. Set either size or time limit to <code>0</code> is invalid.</p></div></div></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><div class="language-java codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-java codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">int</span><span class="token plain"> retentionTime </span><span class="token operator">=</span><span class="token plain"> </span><span class="token number">10</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)">// 10 minutes</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">int</span><span class="token plain"> retentionSize </span><span class="token operator">=</span><span class="token plain"> </span><span class="token number">500</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)">// 500 megabytes</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token class-name">RetentionPolicies</span><span class="token plain"> policies </span><span class="token operator">=</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">new</span><span class="token plain"> </span><span class="token class-name">RetentionPolicies</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">retentionTime</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"> retentionSize</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">admin</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">namespaces</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">setRetention</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">namespace</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"> policies</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></div></div><h3 class="anchor anchorWithStickyNavbar_LWe7" id="get-retention-policy">Get retention policy<a href="#get-retention-policy" class="hash-link" aria-label="Direct link to Get retention policy" title="Direct link to Get retention policy"></a></h3><p>You can fetch the retention policy for a namespace by specifying the namespace. The output will be a JSON object with two keys: <code>retentionTimeInMinutes</code> and <code>retentionSizeInMB</code>.</p><div class="tabs-container tabList__CuJ"><ul role="tablist" aria-orientation="horizontal" class="tabs"><li role="tab" tabindex="0" aria-selected="true" class="tabs__item tabItem_LNqP tabs__item--active">pulsar-admin</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">REST API</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">Java</li></ul><div class="margin-top--md"><div role="tabpanel" class="tabItem_Ymn6"><p>Use the <a href="/reference/#/next/pulsar-admin/namespaces?id=get-retention" target="_blank" rel="noopener noreferrer"><code>get-retention</code></a> subcommand and specify the namespace.</p><h5 class="anchor anchorWithStickyNavbar_LWe7" id="example">Example<a href="#example" class="hash-link" aria-label="Direct link to Example" title="Direct link to Example"></a></h5><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces get-retention my-tenant/my-ns</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">"retentionTimeInMinutes"</span><span class="token builtin class-name" style="color:rgb(189, 147, 249)">:</span><span class="token plain"> </span><span class="token number">10</span><span class="token plain">,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">"retentionSizeInMB"</span><span class="token builtin class-name" style="color:rgb(189, 147, 249)">:</span><span class="token plain"> </span><span class="token number">500</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><p><a href="https://pulsar.apache.org/admin-rest-api?version=3.2.2&apiversion=v2#operation/getRetention" target="_blank" rel="noopener noreferrer">GET /admin/v2/namespaces/:tenant/:namespace/retention/getRetention</a></p></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><div class="language-java codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-java codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">admin</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">namespaces</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">getRetention</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">namespace</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></div></div><h2 class="anchor anchorWithStickyNavbar_LWe7" id="backlog-quotas">Backlog quotas<a href="#backlog-quotas" class="hash-link" aria-label="Direct link to Backlog quotas" title="Direct link to Backlog quotas"></a></h2><p><em>Backlogs</em> are sets of unacknowledged messages for a topic that have been stored by bookies. Pulsar stores all unacknowledged messages in backlogs until they are processed and acknowledged.</p><p>You can control the allowable size and/or time of backlogs, at the namespace level, using <em>backlog quotas</em>. Pulsar uses a quota to enforce a hard limit on the logical size of the backlogs in a topic. Backlog quota triggers an alert policy (for example, producer exception) once the quota limit is reached.</p><p>The diagram below illustrates the concept of backlog quota. |
| <img loading="lazy" alt="Concept of backlog quota in Pulsar" src="/assets/images/backlog-quota-8b858faef29b4f2a73479d396ec5b59f.svg" width="1465" height="907" class="img_ev3q"></p><p>Setting a backlog quota involves setting:</p><ul><li>an allowable <em>size and/or time threshold</em> for each topic in the namespace</li><li>a <em>retention policy</em> that determines which action the <a href="/docs/next/reference-terminology/#broker">broker</a> takes if the threshold is exceeded.</li></ul><p>The following retention policies are available:</p><table><thead><tr><th align="left">Policy</th><th align="left">Action</th></tr></thead><tbody><tr><td align="left"><code>producer_request_hold</code></td><td align="left">The producer holds the message and retris until client configuration <code>sendTimeoutMs</code> is exceeded.</td></tr><tr><td align="left"><code>producer_exception</code></td><td align="left">The producer throws an exception when trying to send a message</td></tr><tr><td align="left"><code>consumer_backlog_eviction</code></td><td align="left">The broker will begin discarding backlog messages</td></tr></tbody></table><blockquote><h4 class="anchor anchorWithStickyNavbar_LWe7" id="beware-the-distinction-between-retention-policy-types">Beware the distinction between retention policy types<a href="#beware-the-distinction-between-retention-policy-types" class="hash-link" aria-label="Direct link to Beware the distinction between retention policy types" title="Direct link to Beware the distinction between retention policy types"></a></h4><p>As you may have noticed, there are two definitions of the term "retention policy" in Pulsar, one that applies to persistent storage of messages not in backlogs, and one that applies to messages within backlogs.</p></blockquote><p>Backlog quotas are handled at the namespace level. They can be managed via:</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="set-sizetime-thresholds-and-backlog-retention-policies">Set size/time thresholds and backlog retention policies<a href="#set-sizetime-thresholds-and-backlog-retention-policies" class="hash-link" aria-label="Direct link to Set size/time thresholds and backlog retention policies" title="Direct link to Set size/time thresholds and backlog retention policies"></a></h3><p>You can set a size and/or time threshold and backlog retention policy for all the topics in a <a href="/docs/next/reference-terminology/#namespace">namespace</a> by specifying the namespace, a size limit and/or a time limit in second, and a policy by name.</p><div class="tabs-container tabList__CuJ"><ul role="tablist" aria-orientation="horizontal" class="tabs"><li role="tab" tabindex="0" aria-selected="true" class="tabs__item tabItem_LNqP tabs__item--active">pulsar-admin</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">REST API</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">Java</li></ul><div class="margin-top--md"><div role="tabpanel" class="tabItem_Ymn6"><p>Use the <a href="/reference/#/next/pulsar-admin/namespaces?id=set-backlog-quota" target="_blank" rel="noopener noreferrer"><code>set-backlog-quota</code></a> subcommand and specify a namespace, a size limit using the <code>-l</code>/<code>--limit</code> , <code>-lt</code>/<code>--limitTime</code> flag to limit backlog, a retention policy using the <code>-p</code>/<code>--policy</code> flag and a policy type using <code>-t</code>/<code>--type</code> (default is destination_storage).</p><h5 class="anchor anchorWithStickyNavbar_LWe7" id="example-1">Example<a href="#example-1" class="hash-link" aria-label="Direct link to Example" title="Direct link to Example"></a></h5><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces set-backlog-quota my-tenant/my-ns </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--limit 2G </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--policy producer_request_hold</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces set-backlog-quota my-tenant/my-ns/my-topic </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--limitTime </span><span class="token number">3600</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--policy producer_request_hold </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--type message_age</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><p><a href="https://pulsar.apache.org/admin-rest-api?version=3.2.2&apiversion=v2#operation/getBacklogQuotaMap" target="_blank" rel="noopener noreferrer">POST /admin/v2/namespaces/:tenant/:namespace/backlogQuota/getBacklogQuotaMap</a></p></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><div class="language-java codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-java codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">admin</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">namespaces</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">setBacklogQuota</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">namespace</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"> </span><span class="token class-name">BacklogQuota</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">builder</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">retentionPolicy</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token class-name">RetentionPolicy</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">producer_request_hold</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">limitSize</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token number">2147483648L</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">limitTime</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token number">60</span><span class="token plain"> </span><span class="token operator">*</span><span class="token plain"> </span><span class="token number">60</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">build</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></div></div><h3 class="anchor anchorWithStickyNavbar_LWe7" id="get-backlog-threshold-and-backlog-retention-policy">Get backlog threshold and backlog retention policy<a href="#get-backlog-threshold-and-backlog-retention-policy" class="hash-link" aria-label="Direct link to Get backlog threshold and backlog retention policy" title="Direct link to Get backlog threshold and backlog retention policy"></a></h3><p>You can see which size threshold and backlog retention policy has been applied to a namespace.</p><div class="tabs-container tabList__CuJ"><ul role="tablist" aria-orientation="horizontal" class="tabs"><li role="tab" tabindex="0" aria-selected="true" class="tabs__item tabItem_LNqP tabs__item--active">pulsar-admin</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">REST API</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">Java</li></ul><div class="margin-top--md"><div role="tabpanel" class="tabItem_Ymn6"><p>Use the <a href="/reference/#/next/pulsar-admin/namespaces?id=get-backlog-quotas" target="_blank" rel="noopener noreferrer"><code>get-backlog-quotas</code></a> subcommand and specify a namespace. Here's an example:</p><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces get-backlog-quotas my-tenant/my-ns</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">"destination_storage"</span><span class="token builtin class-name" style="color:rgb(189, 147, 249)">:</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">"limit"</span><span class="token plain"> </span><span class="token builtin class-name" style="color:rgb(189, 147, 249)">:</span><span class="token plain"> </span><span class="token number">2147483648</span><span class="token plain">,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">"policy"</span><span class="token plain"> </span><span class="token builtin class-name" style="color:rgb(189, 147, 249)">:</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">"producer_request_hold"</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><p><a href="https://pulsar.apache.org/admin-rest-api?version=3.2.2&apiversion=v2#operation/getBacklogQuotaMap" target="_blank" rel="noopener noreferrer">GET /admin/v2/namespaces/:tenant/:namespace/backlogQuotaMap/getBacklogQuotaMap</a></p></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><div class="language-java codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-java codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token class-name">Map</span><span class="token generics punctuation" style="color:rgb(248, 248, 242)"><</span><span class="token generics class-name">BacklogQuota</span><span class="token generics class-name punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token generics class-name">BacklogQuotaType</span><span class="token generics punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token generics class-name">BacklogQuota</span><span class="token generics punctuation" style="color:rgb(248, 248, 242)">></span><span class="token plain"> quotas </span><span class="token operator">=</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> admin</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">namespaces</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">getBacklogQuotas</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">namespace</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></div></div><h3 class="anchor anchorWithStickyNavbar_LWe7" id="monitoring-backlog-quota-usage">Monitoring backlog quota usage<a href="#monitoring-backlog-quota-usage" class="hash-link" aria-label="Direct link to Monitoring backlog quota usage" title="Direct link to Monitoring backlog quota usage"></a></h3><p>The backlog quota limit and usage are exposed both through <a href="/docs/next/reference-metrics/#topic-metrics">metrics</a>, |
| and <a href="/docs/next/administration-stats/#topic-stats">topic stats</a>. This allows to define, for example to define alerts |
| to know ahead of time if a backlog quota is about to reach its limit.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="remove-backlog-quotas">Remove backlog quotas<a href="#remove-backlog-quotas" class="hash-link" aria-label="Direct link to Remove backlog quotas" title="Direct link to Remove backlog quotas"></a></h3><div class="tabs-container tabList__CuJ"><ul role="tablist" aria-orientation="horizontal" class="tabs"><li role="tab" tabindex="0" aria-selected="true" class="tabs__item tabItem_LNqP tabs__item--active">pulsar-admin</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">REST API</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">Java</li></ul><div class="margin-top--md"><div role="tabpanel" class="tabItem_Ymn6"><p>Use the <a href="/reference/#/next/pulsar-admin/namespaces?id=remove-backlog-quota" target="_blank" rel="noopener noreferrer"><code>remove-backlog-quota</code></a> subcommand and specify a namespace, use <code>t</code>/<code>--type</code> to specify backlog type to remove(default is destination_storage). Here's an example:</p><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces remove-backlog-quota my-tenant/my-ns</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><p><a href="https://pulsar.apache.org/admin-rest-api?version=3.2.2&apiversion=v2#operation/removeBacklogQuota" target="_blank" rel="noopener noreferrer">DELETE /admin/v2/namespaces/:tenant/:namespace/backlogQuota/removeBacklogQuota</a></p></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><div class="language-java codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-java codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">admin</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">namespaces</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">removeBacklogQuota</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">namespace</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></div></div><h3 class="anchor anchorWithStickyNavbar_LWe7" id="clear-backlog">Clear backlog<a href="#clear-backlog" class="hash-link" aria-label="Direct link to Clear backlog" title="Direct link to Clear backlog"></a></h3><h4 class="anchor anchorWithStickyNavbar_LWe7" id="pulsar-admin">pulsar-admin<a href="#pulsar-admin" class="hash-link" aria-label="Direct link to pulsar-admin" title="Direct link to pulsar-admin"></a></h4><p>Use the <a href="/reference/#/next/pulsar-admin/namespaces?id=clear-backlog" target="_blank" rel="noopener noreferrer"><code>clear-backlog</code></a> subcommand.</p><h5 class="anchor anchorWithStickyNavbar_LWe7" id="example-2">Example<a href="#example-2" class="hash-link" aria-label="Direct link to Example" title="Direct link to Example"></a></h5><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces clear-backlog my-tenant/my-ns</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div><p>By default, you will be prompted to ensure that you want to clear the backlog for the namespace. You can override the prompt using the <code>-f</code>/<code>--force</code> flag.</p><h2 class="anchor anchorWithStickyNavbar_LWe7" id="time-to-live-ttl">Time to live (TTL)<a href="#time-to-live-ttl" class="hash-link" aria-label="Direct link to Time to live (TTL)" title="Direct link to Time to live (TTL)"></a></h2><p>By default, Pulsar stores all unacknowledged messages forever. This can lead to heavy disk space usage in cases where a lot of messages are going unacknowledged. If disk space is a concern, you can set a time to live (TTL) that determines how long unacknowledged messages will be retained.</p><p>The TTL parameter is like a stopwatch attached to each message that defines the amount of time a message is allowed to stay unacknowledged. When the TTL expires, Pulsar automatically moves the message to the acknowledged state (and thus makes it ready for deletion).</p><p>The diagram below illustrates the concept of TTL. |
| <img loading="lazy" alt="Concept of TTL in Pulsar" src="/assets/images/ttl-7605af453040d419a432d79d41b23830.svg" width="1100" height="581" class="img_ev3q"></p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="set-the-ttl-for-a-namespace">Set the TTL for a namespace<a href="#set-the-ttl-for-a-namespace" class="hash-link" aria-label="Direct link to Set the TTL for a namespace" title="Direct link to Set the TTL for a namespace"></a></h3><div class="tabs-container tabList__CuJ"><ul role="tablist" aria-orientation="horizontal" class="tabs"><li role="tab" tabindex="0" aria-selected="true" class="tabs__item tabItem_LNqP tabs__item--active">pulsar-admin</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">REST API</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">Java</li></ul><div class="margin-top--md"><div role="tabpanel" class="tabItem_Ymn6"><p>Use the <a href="/reference/#/next/pulsar-admin/namespaces?id=set-message-ttl" target="_blank" rel="noopener noreferrer"><code>set-message-ttl</code></a> subcommand and specify a namespace and a TTL (in seconds) using the <code>-ttl</code>/<code>--messageTTL</code> flag.</p><h5 class="anchor anchorWithStickyNavbar_LWe7" id="example-3">Example<a href="#example-3" class="hash-link" aria-label="Direct link to Example" title="Direct link to Example"></a></h5><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces set-message-ttl my-tenant/my-ns </span><span class="token punctuation" style="color:rgb(248, 248, 242)">\</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">--messageTTL </span><span class="token number">120</span><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)"># TTL of 2 minutes</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><p><a href="https://pulsar.apache.org/admin-rest-api?version=3.2.2&apiversion=v2#operation/setNamespaceMessageTTL" target="_blank" rel="noopener noreferrer">POST /admin/v2/namespaces/:tenant/:namespace/messageTTL/setNamespaceMessageTTL</a></p></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><div class="language-java codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-java codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">admin</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">namespaces</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">setNamespaceMessageTTL</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">namespace</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"> ttlInSeconds</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></div></div><h3 class="anchor anchorWithStickyNavbar_LWe7" id="get-the-ttl-configuration-for-a-namespace">Get the TTL configuration for a namespace<a href="#get-the-ttl-configuration-for-a-namespace" class="hash-link" aria-label="Direct link to Get the TTL configuration for a namespace" title="Direct link to Get the TTL configuration for a namespace"></a></h3><div class="tabs-container tabList__CuJ"><ul role="tablist" aria-orientation="horizontal" class="tabs"><li role="tab" tabindex="0" aria-selected="true" class="tabs__item tabItem_LNqP tabs__item--active">pulsar-admin</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">REST API</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">Java</li></ul><div class="margin-top--md"><div role="tabpanel" class="tabItem_Ymn6"><p>Use the <a href="/reference/#/next/pulsar-admin/namespaces?id=get-message-ttl" target="_blank" rel="noopener noreferrer"><code>get-message-ttl</code></a> subcommand and specify a namespace.</p><h5 class="anchor anchorWithStickyNavbar_LWe7" id="example-4">Example<a href="#example-4" class="hash-link" aria-label="Direct link to Example" title="Direct link to Example"></a></h5><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces get-message-ttl my-tenant/my-ns</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token number">60</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><p><a href="https://pulsar.apache.org/admin-rest-api?version=3.2.2&apiversion=v2#operation/getNamespaceMessageTTL" target="_blank" rel="noopener noreferrer">GET /admin/v2/namespaces/:tenant/:namespace/messageTTL/getNamespaceMessageTTL</a></p></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><div class="language-java codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-java codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">admin</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">namespaces</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">getNamespaceMessageTTL</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">namespace</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></div></div><h3 class="anchor anchorWithStickyNavbar_LWe7" id="remove-the-ttl-configuration-for-a-namespace">Remove the TTL configuration for a namespace<a href="#remove-the-ttl-configuration-for-a-namespace" class="hash-link" aria-label="Direct link to Remove the TTL configuration for a namespace" title="Direct link to Remove the TTL configuration for a namespace"></a></h3><div class="tabs-container tabList__CuJ"><ul role="tablist" aria-orientation="horizontal" class="tabs"><li role="tab" tabindex="0" aria-selected="true" class="tabs__item tabItem_LNqP tabs__item--active">pulsar-admin</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">REST API</li><li role="tab" tabindex="-1" aria-selected="false" class="tabs__item tabItem_LNqP">Java</li></ul><div class="margin-top--md"><div role="tabpanel" class="tabItem_Ymn6"><p>Use the <a href="/reference/#/next/pulsar-admin/namespaces?id=remove-message-ttl" target="_blank" rel="noopener noreferrer"><code>remove-message-ttl</code></a> subcommand and specify a namespace.</p><h5 class="anchor anchorWithStickyNavbar_LWe7" id="example-5">Example<a href="#example-5" class="hash-link" aria-label="Direct link to Example" title="Direct link to Example"></a></h5><div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">pulsar-admin namespaces remove-message-ttl my-tenant/my-ns</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><p><a href="https://pulsar.apache.org/admin-rest-api?version=3.2.2&apiversion=v2#operation/removeNamespaceMessageTTL" target="_blank" rel="noopener noreferrer">DELETE /admin/v2/namespaces/:tenant/:namespace/messageTTL/removeNamespaceMessageTTL</a></p></div><div role="tabpanel" class="tabItem_Ymn6" hidden=""><div class="language-java codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-java codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">admin</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">namespaces</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">removeNamespaceMessageTTL</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">namespace</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg class="copyButtonIcon_y97N" viewBox="0 0 24 24"><path d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg class="copyButtonSuccessIcon_LjdS" viewBox="0 0 24 24"><path d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></div></div><h2 class="anchor anchorWithStickyNavbar_LWe7" id="delete-messages-from-namespaces">Delete messages from namespaces<a href="#delete-messages-from-namespaces" class="hash-link" aria-label="Direct link to Delete messages from namespaces" title="Direct link to Delete messages from namespaces"></a></h2><p>When it comes to the physical storage size, message expiry and retention are just like two sides of the same coin.</p><ul><li>The backlog quota and TTL parameters prevent disk size from growing indefinitely, as Pulsar's default behavior is to persist unacknowledged messages.</li><li>The retention policy allocates storage space to accommodate the messages that are supposed to be deleted by Pulsar by default.</li></ul><p>In conclusion, the size of your physical storage should accommodate the sum of the backlog quota and the retention size.</p><p>The message deletion rate (releasing rate of disk space) can be determined by multiple factors.</p><ul><li><p><strong>Segment rollover period</strong>: basically, the segment rollover period is how often a new segment is created. Once a new segment is created, the old segment will be deleted. By default, this happens either when you have written 50,000 entries (messages) or have waited 240 minutes. You can tune this in your broker.</p></li><li><p><strong>Entry log rollover period</strong>: multiple ledgers in BookKeeper are interleaved into an <a href="https://bookkeeper.apache.org/docs/4.11.1/getting-started/concepts/#entry-logs" target="_blank" rel="noopener noreferrer">entry log</a>. In order for a ledger that has been deleted, the entry log must all be rolled over. |
| The entry log rollover period is configurable but is purely based on the entry log size. For details, see <a href="https://bookkeeper.apache.org/docs/4.11.1/reference/config/#entry-log-settings" target="_blank" rel="noopener noreferrer">here</a>. Once the entry log is rolled over, the entry log can be garbage collected.</p></li><li><p><strong>Garbage collection interval</strong>: because entry logs have interleaved ledgers, to free up space, the entry logs need to be rewritten. The garbage collection interval is how often BookKeeper performs garbage collection. which is related to minor compaction and major compaction of entry logs. For details, see <a href="https://bookkeeper.apache.org/docs/4.11.1/reference/config/#entry-log-compaction-settings" target="_blank" rel="noopener noreferrer">here</a>.</p></li></ul><p>The diagram below illustrates one of the cases that the consumed storage size is larger than the given limits for backlog and retention. Messages over the retention limit are kept because other messages in the same segment are still within retention period. |
| <img loading="lazy" alt="Message expiry and retention in Pulsar" src="/assets/images/retention-storage-size-4c7f0e9aa49ebd431dae787dd13b60ba.svg" width="1159" height="614" class="img_ev3q"></p><p>If you do not have any retention period and you never have much of a backlog, the upper limit for retained messages, which are acknowledged, equals the Pulsar segment rollover period + entry log rollover period + (garbage collection interval * garbage collection ratios).</p></div><footer class="theme-doc-footer docusaurus-mt-lg"><div class="theme-doc-footer-edit-meta-row row"><div class="col"><a href="https://github.com/apache/pulsar-site/edit/main/docs/cookbooks-retention-expiry.md" target="_blank" rel="noreferrer noopener" class="theme-edit-this-page"><svg fill="currentColor" height="20" width="20" viewBox="0 0 40 40" class="iconEdit_Z9Sw" aria-hidden="true"><g><path d="m34.5 11.7l-3 3.1-6.3-6.3 3.1-3q0.5-0.5 1.2-0.5t1.1 0.5l3.9 3.9q0.5 0.4 0.5 1.1t-0.5 1.2z m-29.5 17.1l18.4-18.5 6.3 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