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id="motivation">Motivation<a href="#motivation" class="hash-link" aria-label="Direct link to Motivation" title="Direct link to Motivation"></a></h3><p>Each time the cluster triggers the re-replication, all replicators will read data from zookeeper. This can cause a great
 pressure on Zookeeper. We need to support throttling for zookeeper read of re-replication.</p><p>For example, in a Pulsar cluster, we enable auto-recovery for every bookie. There are 400 bookies in a cluster, which
 means there are 400 replicators in the cluster.
 And there are about 3000 ledgers in each bookie, 1/3 of them are small ledgers, whose size is less than 0.1MB, that is
 1000 small ledgers in each bookie.
 If one bookie is decommissioned, the read latency of zookeeper will increase to minutes.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="configuration">Configuration<a href="#configuration" class="hash-link" aria-label="Direct link to Configuration" title="Direct link to Configuration"></a></h3><p>add the following configuration:</p><div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token plain">zkReplicationTaskRateLimit</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>default value is 0, which means no limit.
 Value greater than 0 will enable the rate limit, and the value is the number of tasks that can be acquired per second.
 Decimals are allowed too, for example, 0.5 means 1 task every 2 seconds, 1 means 1 task per second, 2 means 2 tasks per
 second, and so on.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="proposed-changes">Proposed Changes<a href="#proposed-changes" class="hash-link" aria-label="Direct link to Proposed Changes" title="Direct link to Proposed Changes"></a></h3><p>Add a new configuration <code>zkReplicationTaskRateLimit</code> to control the rate of zookeeper read of re-replication.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="compatibility-deprecation-and-migration-plan">Compatibility, Deprecation, and Migration Plan<a href="#compatibility-deprecation-and-migration-plan" class="hash-link" aria-label="Direct link to Compatibility, Deprecation, and Migration Plan" title="Direct link to Compatibility, Deprecation, and Migration Plan"></a></h3><p>Full compatibility with the existing behavior. No deprecation needed.</p></article></div><div class="col col--2"><div class="tableOfContents_bqdL thin-scrollbar"><ul class="table-of-contents table-of-contents__left-border"><li><a href="#motivation" class="table-of-contents__link toc-highlight">Motivation</a></li><li><a href="#configuration" class="table-of-contents__link toc-highlight">Configuration</a></li><li><a href="#proposed-changes" class="table-of-contents__link toc-highlight">Proposed Changes</a></li><li><a href="#compatibility-deprecation-and-migration-plan" class="table-of-contents__link toc-highlight">Compatibility, Deprecation, and Migration Plan</a></li></ul></div></div></div></main></div><footer class="footer footer--dark"><div class="container container-fluid"><div class="row footer__links"><div class="col footer__col"><div class="footer__title">Documentation</div><ul class="footer__items clean-list"><li class="footer__item"><a class="footer__link-item" href="/docs/overview">Overview</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/getting-started/installation">Getting started</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/deployment/manual">Deployment</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/admin/bookies">Administration</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/api/overview">API</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/security/overview">Security</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/development/protocol">Development</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/reference/config">Reference</a></li></ul></div><div class="col footer__col"><div class="footer__title">Community</div><ul class="footer__items clean-list"><li class="footer__item"><a class="footer__link-item" href="/community/mailing-lists">Mailing lists</a></li><li class="footer__item"><a class="footer__link-item" href="/community/slack">Slack</a></li><li class="footer__item"><a href="https://github.com/apache/bookkeeper" target="_blank" rel="noopener noreferrer" class="footer__link-item">Github<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://twitter.com/asfbookkeeper" target="_blank" rel="noopener noreferrer" class="footer__link-item">Twitter<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li></ul></div><div class="col footer__col"><div class="footer__title">Project</div><ul class="footer__items clean-list"><li class="footer__item"><a class="footer__link-item" href="/project/who">Who are we?</a></li><li class="footer__item"><a class="footer__link-item" href="/project/bylaws">Bylaws</a></li><li class="footer__item"><a href="https://apache.org/licenses" target="_blank" rel="noopener noreferrer" class="footer__link-item">License<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a class="footer__link-item" href="/project/privacy">Privacy policy</a></li><li class="footer__item"><a href="https://www.apache.org/foundation/sponsorship.html" target="_blank" rel="noopener noreferrer" class="footer__link-item">Sponsorship<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://www.apache.org/foundation/thanks.html" target="_blank" rel="noopener noreferrer" class="footer__link-item">Thanks<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li></ul></div></div><div class="footer__bottom text--center"><div class="footer__copyright"><footer class="footer">
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id="motivation">Motivation<a href="#motivation" class="hash-link" aria-label="Direct link to Motivation" title="Direct link to Motivation"></a></h3><p>Each time the cluster triggers the re-replication, all replicators will read data from zookeeper. This can cause a great
	pressure on Zookeeper. We need to support throttling for zookeeper read of re-replication.</p><p>For example, in a Pulsar cluster, we enable auto-recovery for every bookie. There are 400 bookies in a cluster, which
	means there are 400 replicators in the cluster.
	And there are about 3000 ledgers in each bookie, 1/3 of them are small ledgers, whose size is less than 0.1MB, that is
	1000 small ledgers in each bookie.
	If one bookie is decommissioned, the read latency of zookeeper will increase to minutes.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="configuration">Configuration<a href="#configuration" class="hash-link" aria-label="Direct link to Configuration" title="Direct link to Configuration"></a></h3><p>add the following configuration:</p><div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token plain">zkReplicationTaskRateLimit</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>default value is 0, which means no limit.
	Value greater than 0 will enable the rate limit, and the value is the number of tasks that can be acquired per second.
	Decimals are allowed too, for example, 0.5 means 1 task every 2 seconds, 1 means 1 task per second, 2 means 2 tasks per
	second, and so on.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="proposed-changes">Proposed Changes<a href="#proposed-changes" class="hash-link" aria-label="Direct link to Proposed Changes" title="Direct link to Proposed Changes"></a></h3><p>Add a new configuration <code>zkReplicationTaskRateLimit</code> to control the rate of zookeeper read of re-replication.</p><h3 class="anchor anchorWithStickyNavbar_LWe7" id="compatibility-deprecation-and-migration-plan">Compatibility, Deprecation, and Migration Plan<a href="#compatibility-deprecation-and-migration-plan" class="hash-link" aria-label="Direct link to Compatibility, Deprecation, and Migration Plan" title="Direct link to Compatibility, Deprecation, and Migration Plan"></a></h3><p>Full compatibility with the existing behavior. No deprecation needed.</p></article></div><div class="col col--2"><div class="tableOfContents_bqdL thin-scrollbar"><ul class="table-of-contents table-of-contents__left-border"><li><a href="#motivation" class="table-of-contents__link toc-highlight">Motivation</a></li><li><a href="#configuration" class="table-of-contents__link toc-highlight">Configuration</a></li><li><a href="#proposed-changes" class="table-of-contents__link toc-highlight">Proposed Changes</a></li><li><a href="#compatibility-deprecation-and-migration-plan" class="table-of-contents__link toc-highlight">Compatibility, Deprecation, and Migration Plan</a></li></ul></div></div></div></main></div><footer class="footer footer--dark"><div class="container container-fluid"><div class="row footer__links"><div class="col footer__col"><div class="footer__title">Documentation</div><ul class="footer__items clean-list"><li class="footer__item"><a class="footer__link-item" href="/docs/overview">Overview</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/getting-started/installation">Getting started</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/deployment/manual">Deployment</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/admin/bookies">Administration</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/api/overview">API</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/security/overview">Security</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/development/protocol">Development</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/reference/config">Reference</a></li></ul></div><div class="col footer__col"><div class="footer__title">Community</div><ul class="footer__items clean-list"><li class="footer__item"><a class="footer__link-item" href="/community/mailing-lists">Mailing lists</a></li><li class="footer__item"><a class="footer__link-item" href="/community/slack">Slack</a></li><li class="footer__item"><a href="https://github.com/apache/bookkeeper" target="_blank" rel="noopener noreferrer" class="footer__link-item">Github<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://twitter.com/asfbookkeeper" target="_blank" rel="noopener noreferrer" class="footer__link-item">Twitter<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li></ul></div><div class="col footer__col"><div class="footer__title">Project</div><ul class="footer__items clean-list"><li class="footer__item"><a class="footer__link-item" href="/project/who">Who are we?</a></li><li class="footer__item"><a class="footer__link-item" href="/project/bylaws">Bylaws</a></li><li class="footer__item"><a href="https://apache.org/licenses" target="_blank" rel="noopener noreferrer" class="footer__link-item">License<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a class="footer__link-item" href="/project/privacy">Privacy policy</a></li><li class="footer__item"><a href="https://www.apache.org/foundation/sponsorship.html" target="_blank" rel="noopener noreferrer" class="footer__link-item">Sponsorship<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://www.apache.org/foundation/thanks.html" target="_blank" rel="noopener noreferrer" class="footer__link-item">Thanks<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li></ul></div></div><div class="footer__bottom text--center"><div class="footer__copyright"><footer class="footer">
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