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| |
| <html> |
| <head> |
| <meta name="viewport" content="width=device-width, initial-scale=1"> |
| <title>PageSpeed Console</title> |
| <link rel="stylesheet" href="doc.css"> |
| </head> |
| <body> |
| <!--#include virtual="_header.html" --> |
| |
| |
| <div id=content> |
| <h1>PageSpeed Console</h1> |
| <h2 id="about">About the Console</h2> |
| <p> |
| The PageSpeed Console reports various problems your installation has that can |
| lead to sub-optimal performance. The console graphs metrics for these |
| problems over time so that you can see the result of your changes |
| improving or degrading your performance. You can view it by enabling it and |
| then visiting <code>/pagespeed_admin/console</code> from your server. The |
| console works by saving snapshots of the statistics reported by |
| PageSpeed and then using the Google Chart Tools API to graph those |
| statistics over time. |
| <h2 id="configuring">Configuring the Console</h2> |
| <p> |
| The PageSpeed Console is configured with several directives in the |
| configuration file. See |
| <a href="install#module">PageSpeed Installation and Configuration</a> |
| for details about this file. Each of these directives is explained here. |
| </p> |
| <ul> |
| <li> |
| <code><a href="admin#statistics">Statistics</a></code> |
| must be enabled to report statistics.</li> |
| <li> |
| <code>StatisticsLogging</code> must be enabled so that graphs of |
| statistics over time can be drawn in the console.</li> |
| <li> |
| <code>LogDir</code> must be set so that we have a directory to store |
| statistic logs.</li> |
| <li> |
| In order to access the console, you must set a handler appropriately. |
| For example, to make the console only accessible from localhost: |
| <dl> |
| <dt>Apache:<dd><pre> |
| ModPagespeedStatistics on |
| ModPagespeedStatisticsLogging on |
| ModPagespeedLogDir /var/log/pagespeed |
| <Location /pagespeed_admin> |
| Order allow,deny |
| Allow from localhost |
| Allow from 127.0.0.1 |
| SetHandler pagespeed_admin |
| </Location></pre> |
| <dt>Nginx:<dd><pre> |
| pagespeed Statistics on; |
| pagespeed StatisticsLogging on; |
| pagespeed LogDir /var/log/pagespeed; |
| pagespeed AdminPath /pagespeed_admin; |
| |
| location ~ ^/pagespeed_admin { |
| allow 127.0.0.1; |
| deny all; |
| }</pre> |
| </dl> |
| </li> |
| </ul> |
| <p> |
| Additionally these optional parameters may be configured: |
| </p> |
| <ul> |
| <li> |
| <code>StatisticsLoggingIntervalMs</code> may be set to indicate how often |
| to log statistics snapshots (in milliseconds).</li> |
| <li> |
| <code>StatisticsLoggingMaxFileSizeKb</code> may be set to indicate the |
| maximum size for the logfile (in kilobytes).</li> |
| </ul> |
| <p> |
| For example, to log once a minute with a maximum log size of 1 MB: |
| </p> |
| <dl> |
| <dt>Apache:<dd><pre> |
| ModPagespeedStatisticsLoggingIntervalMs 60000 |
| ModPagespeedStatisticsLoggingMaxFileSizeKb 1024</pre> |
| <dt>Nginx:<dd><pre> |
| pagespeed StatisticsLoggingIntervalMs 60000; |
| pagespeed StatisticsLoggingMaxFileSizeKb 1024;</pre> |
| </dl> |
| |
| <h2 id="access">Accessing the Console</h2> |
| <p> |
| The console can be accessed by browsing to |
| <code>http://your.example.com/pagespeed_admin/console</code>. Access to |
| this page can be controlled using standard access directives. |
| </p> |
| <p> |
| Note that if you would like to access the console from machines other |
| than your server, you will need to allow access to |
| <code>/pagespeed_admin</code>. |
| </p> |
| |
| <!-- TODO(sligocki): Add section for features, like zooming in, etc. once we |
| add them. --> |
| |
| <h2 id="graphs">Graphed metrics</h2> |
| The PageSpeed console displays graphs for these metrics: |
| <ul> |
| <li id="fetch-failure"> |
| <b>Resources not loaded because of fetch failures</b>: |
| Images, CSS or JavaScript could not be loaded because backend HTTP fetch |
| failed. <b>Remedy</b>: You may have to reconfigure your server to allow |
| outgoing connections or to have access to DNS.</li> |
| |
| <li id="not-authorized"> |
| <b>Resources not rewritten because domain wasn't authorized</b>: |
| Resources could not be rewritten because they were on a different domain |
| than the HTML and that domain was not explicitly authorized. |
| <b>Remedy</b>: Add <a href="domains#auth_domains">Domain</a> |
| authorizations for all domains you control.</li> |
| |
| <li id="cache-control"> |
| <b>Resources not rewritten because of restrictive Cache-Control headers</b>: |
| Resources could not be rewritten because they had restrictive Cache-Control |
| headers explicitly set (for example: <code>Cache-Control: private</code>, |
| <code>Cache-Control: max-age=0</code> or |
| <code>Cache-Control: no-transform</code>). |
| <b>Remedy</b>: Reconfigure your server to serve these resources with |
| public caching headers (or no Cache-Control headers at all). For example, |
| <code>Header set Cache-Control "max-age=600"</code> in Apache config.</li> |
| |
| <li id="cache-miss"> |
| <b>Cache misses</b>: |
| Resources were not rewritten because they were not found in cache. |
| This is expected while your cache warms up, soon after you install, however |
| if it continues to be high, your cache is probably too small. |
| <b>Remedy</b>: Increase the |
| <a href="system#file_cache">FileCacheSizeKb</a> to be about 5 times |
| as large as your website content (to store all of the original |
| resources and various versions of rewritten resources).</li> |
| |
| <li id="cache-expired"> |
| <b>Cache lookups that were expired</b>: |
| Although these resources were found in cache, they were not rewritten |
| because they were older than their max-age. |
| <b>Remedy</b>: (A) Enable |
| <a href="domains#ModPagespeedLoadFromFile">LoadFromFile</a> to tell |
| the server to load the files straight from disk rather than through |
| HTTP. (B) Reconfigure your server to serve resources with longer TTL. |
| For example, <code>Header set Cache-Control "max-age=3600"</code> to set |
| one hour TTL in Apache config.</li> |
| |
| <li id="css-error"> |
| <b>CSS files not rewritten because of parse errors</b>: |
| CSS files could not be rewritten because our parser found syntax errors |
| that it could not recover from. <b>Remedy</b>: Fix CSS files to use |
| proper syntax. You can use the stand-alone |
| <a href="build_mod_pagespeed_from_source#debug-css">css_minify_main</a> |
| to find what part of the CSS file has parse errors. We have had some |
| problems in the past with valid CSS3 or proprietary CSS extensions |
| causing CSS parsing errors. If you find that your valid CSS is failing to |
| parse, let us know on our <a href="mailing-lists#discussion">discussion |
| group</a> so we can fix the parser.</li> |
| |
| <li id="js-error"> |
| <b>JavaScript minification failures</b>: |
| JavaScript files could not be minified because our parser found some |
| syntax problem that it could not recover from. This is very uncommon. |
| <b>Remedy</b>: As with CSS, fix the JavaScript files that had problems.</li> |
| |
| <li id="image-error"> |
| <b>Image rewrite failures</b>: |
| Image files were not rewritten for various reasons:<ul> |
| <li><code>image_norewrites_high_resolution</code>: Image was too large. |
| Currently we only rewrite images below 8 Megapixels. |
| <b>Remedy</b>: Resize original images to a reasonable size.</li> |
| <li><code>image_rewrites_dropped_decode_failure</code>: Image could not |
| be parsed by our code. <b>Remedy</b>: Fix malformed images.</li> |
| <li><code>image_rewrites_dropped_due_to_load</code>: Image was not |
| rewritten because your system was already busy rewriting other images. |
| This generally can happen when you first install PageSpeed |
| while the cache warms up. <b>Remedy</b>: If image rewrites continue |
| to be dropped after a day or so, you may need to |
| <a href="#cache-miss">increase your cache size</a> or increase the |
| <a href="reference-image-optimize#ImageMaxRewritesAtOnce"> |
| ImageMaxRewritesAtOnce</a>.</li> |
| <li><code>image_rewrites_dropped_mime_type_unknown</code>: Image could |
| not be rewritten because we do not recognize its MIME-type. For |
| example, we do not parse <code>image/x-icon</code> or |
| <code>image/svg+xml</code>. <b>Remedy</b>: Convert your images to a |
| type that we understand (gif, png, jpg, webp) or perhaps just fix |
| a broken server config that is serving images with a bogus |
| <code>Content-Type</code> header.</li> |
| <li><code>image_rewrites_dropped_server_write_fail</code>: Unexpected |
| server error while rewriting images. If you get a significant number |
| of these write to our <a href="mailing-lists#discussion">discussion |
| group</a> so we can investigate.</li> |
| </ul> |
| </li> |
| </ul> |
| |
| </div> |
| <!--#include virtual="_footer.html" --> |
| </body> |
| </html> |
