forked from docs/doc-exports
Lu, Huayi
a24ca60074
Reviewed-by: Hasko, Vladimir <vladimir.hasko@t-systems.com> Co-authored-by: Lu, Huayi <luhuayi@huawei.com> Co-committed-by: Lu, Huayi <luhuayi@huawei.com>
92 lines
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92 lines
24 KiB
HTML
<a name="EN-US_TOPIC_0000001145814611"></a><a name="EN-US_TOPIC_0000001145814611"></a>
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<h1 class="topictitle1">Automatic Cleanup</h1>
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<div id="body8662426"><p id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778244_p595074117714">The automatic cleanup process (autovacuum) in the system automatically runs the <strong id="EN-US_TOPIC_0000001145814611__b147932253834649">VACUUM</strong> and <strong id="EN-US_TOPIC_0000001145814611__b140381129034649">ANALYZE</strong> commands to recycle the record space marked by the deleted status and update statistics in the table.</p>
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<div class="section" id="EN-US_TOPIC_0000001145814611__s8d6c38309e594a16a07f79ae412b63c6"><h4 class="sectiontitle">autovacuum</h4><p id="EN-US_TOPIC_0000001145814611__ae4f6f9442dd546139c63415f9d833b32"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0085032001_en-us_topic_0059778244_en-us_topic_0058967612_b45233644">Parameter description</strong>: Enables the automatic cleanup process (autovacuum) in the database. Ensure that the <a href="dws_04_0920.html#EN-US_TOPIC_0000001098974554__s4682d08468f84845bfdc6ae9477126e8">track_counts</a> parameter is set to <strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0085032001_en-us_topic_0058967612_b842352706111449">on</strong> before enabling the automatic cleanup process.</p>
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<p id="EN-US_TOPIC_0000001145814611__p440031729"><strong id="EN-US_TOPIC_0000001145814611__b179783022418">Type</strong>: SIGHUP</p>
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<div class="note" id="EN-US_TOPIC_0000001145814611__n6b3069381a084e049751b6e6e0a83566"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><ul id="EN-US_TOPIC_0000001145814611__u7c9f4b2825a44913b2d330ac15047026"><li id="EN-US_TOPIC_0000001145814611__l994d14970c204569a134a87348899de3">Set the <strong id="EN-US_TOPIC_0000001145814611__b13206556124311">autovacuum</strong> parameter to <strong id="EN-US_TOPIC_0000001145814611__b842352706183654">on</strong> if you want to enable the function to automatically clean up two-phase transactions after the system recovers from faults.</li><li id="EN-US_TOPIC_0000001145814611__l2ed94009fc62494583ad06aa6419edf6">If <strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0085032001_b842352706183728">autovacuum</strong> is set to <strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0085032001_b842352706183733">on</strong> and the value of <a href="#EN-US_TOPIC_0000001145814611__s502d4304994d4da5bd3cda661aab27ac">autovacuum_max_workers</a> is <strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0085032001_b84235270618389">0</strong>, the system will not automatically clean up two-phase transactions. The system will clean up them after recovering from faults.</li><li id="EN-US_TOPIC_0000001145814611__lb0f9644ce8c14966b7c4a2ccb5329943">If <strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0085032001_b842352706184052">autovacuum</strong> is set to <strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0085032001_b842352706184059">on</strong> and the value of <a href="#EN-US_TOPIC_0000001145814611__s502d4304994d4da5bd3cda661aab27ac">autovacuum_max_workers</a> is greater than <strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0085032001_b842352706184123">0</strong>, the system will automatically clean up the two-phase transactions and processes after recovering from faults.</li></ul>
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</div></div>
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<div class="notice" id="EN-US_TOPIC_0000001145814611__ne7dee8ee88ce4d6299b8651b0fa820d1"><span class="noticetitle"><img src="public_sys-resources/notice_3.0-en-us.png"> </span><div class="noticebody"><p id="EN-US_TOPIC_0000001145814611__ad4dcecad45244b479ca36477091d3a4a">Even if the <strong id="EN-US_TOPIC_0000001145814611__b1953781217447">autovacuum</strong> parameter is set to <strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0085032001_b842352706184153">off</strong>, the automatic cleanup process will be enabled automatically by the database when a transaction ID wrap is about to occur. When the create database or drop database operation fails, some nodes may be submitted or rolled back while others in the prepared status may not be submitted. In this case, the system cannot automatically restore these nodes and the manual restoration is required. The restoration steps are as follows:</p>
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<ol id="EN-US_TOPIC_0000001145814611__of6753c2ec2144f15a4101587b4a16259"><li id="EN-US_TOPIC_0000001145814611__l30d6586b2b5e42698444024723fb6ca2">Use the <strong id="EN-US_TOPIC_0000001145814611__b842352706204616">gs_clean</strong> tool (setting the <strong id="EN-US_TOPIC_0000001145814611__b32691385734649">option</strong> parameter to <strong id="EN-US_TOPIC_0000001145814611__b842352706184340">-N</strong>) to query the xid of the abnormal two-phase transactions and nodes in the prepared state.</li><li id="EN-US_TOPIC_0000001145814611__l266d511aae084192a6a331973e103e6c">Log in to the nodes whose transactions are in the prepared status. Administrators connect to an available database such as <span id="EN-US_TOPIC_0000001145814611__text147259218363">gaussdb</span> to run the <strong id="EN-US_TOPIC_0000001145814611__b1055182534514">set xc_maintenance_mode = on</strong> statement.</li><li id="EN-US_TOPIC_0000001145814611__l674cdbd0c49a4346a5051dca9fa87d5a">Submit or roll back the two-phase transactions (for example, submit or roll back a statement) based on global transaction status.</li></ol>
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</div></div>
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<p id="EN-US_TOPIC_0000001145814611__a871c10cb81fd4bee993a9cf00c5a91db"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778244_en-us_topic_0058967612_b31827961">Value range</strong>: Boolean</p>
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<ul id="EN-US_TOPIC_0000001145814611__u9679d3fef2e1466aba7688aaff1fe697"><li id="EN-US_TOPIC_0000001145814611__lf92a3833049d4520827451527707b616"><strong id="EN-US_TOPIC_0000001145814611__b842352706143336">on</strong> indicates the database automatic cleanup process is enabled.</li><li id="EN-US_TOPIC_0000001145814611__la3dcfb6c9bbb4eeb9e696b70f27541b6"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0085032001_b842352706143336">off</strong> indicates the database automatic cleanup process is disabled.</li></ul>
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<p id="EN-US_TOPIC_0000001145814611__afabfb506ed1243d18f3e87ff552e5d65"><strong id="EN-US_TOPIC_0000001145814611__b25585163445">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__b95631516174416">off</strong></p>
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</div>
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<div class="section" id="EN-US_TOPIC_0000001145814611__section658130152017"><h4 class="sectiontitle">autovacuum_mode</h4><p id="EN-US_TOPIC_0000001145814611__p844791210525"><strong id="EN-US_TOPIC_0000001145814611__b057401215164">Parameter description</strong>: Specifies whether the autoanalyze or autovacuum function is enabled. This parameter is valid only when <strong id="EN-US_TOPIC_0000001145814611__b341225612161">autovacuum</strong> is set to <strong id="EN-US_TOPIC_0000001145814611__b207751457191614">on</strong>.</p>
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<p id="EN-US_TOPIC_0000001145814611__p11716202593316"><strong id="EN-US_TOPIC_0000001145814611__b8366740112518">Type</strong>: SIGHUP</p>
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<p id="EN-US_TOPIC_0000001145814611__p1488218235493"><strong id="EN-US_TOPIC_0000001145814611__b688412236498">Value range</strong>: enumerated values</p>
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<ul id="EN-US_TOPIC_0000001145814611__ul1688422312497"><li id="EN-US_TOPIC_0000001145814611__li96231727051"><strong id="EN-US_TOPIC_0000001145814611__b1210712111174">analyze</strong> indicates that only autoanalyze is performed.</li><li id="EN-US_TOPIC_0000001145814611__li155761262"><strong id="EN-US_TOPIC_0000001145814611__b1438311223170">vacuum</strong> indicates that only autovacuum is performed.</li><li id="EN-US_TOPIC_0000001145814611__li39952131464"><strong id="EN-US_TOPIC_0000001145814611__b946503111179">mix</strong> indicates that both autoanalyze and autovacuum are performed.</li><li id="EN-US_TOPIC_0000001145814611__li1188442316495"><strong id="EN-US_TOPIC_0000001145814611__b14199939151712">none</strong> indicates that neither of them is performed.</li></ul>
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<p id="EN-US_TOPIC_0000001145814611__p1887102354914"><strong id="EN-US_TOPIC_0000001145814611__b6524743191316">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__b1481246131313">mix</strong></p>
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</div>
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<div class="section" id="EN-US_TOPIC_0000001145814611__section11642162416185"><h4 class="sectiontitle">autoanalyze_timeout</h4><p id="EN-US_TOPIC_0000001145814611__p1168744216181"><strong id="EN-US_TOPIC_0000001145814611__b15200164714174">Parameter description</strong>: Specifies the timeout period of autoanalyze. If the duration of autoanalyze on a table exceeds the value of <strong id="EN-US_TOPIC_0000001145814611__b1888193218183">autoanalyze_timeout</strong>, the autoanalyze is automatically canceled.</p>
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<p id="EN-US_TOPIC_0000001145814611__p4287171810334"><strong id="EN-US_TOPIC_0000001145814611__b1445784014255">Type</strong>: SIGHUP</p>
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<p id="EN-US_TOPIC_0000001145814611__p1543044916184"><strong id="EN-US_TOPIC_0000001145814611__b3670177132412">Value range</strong>: an integer ranging from 0 to 2147483. The unit is second.</p>
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<p id="EN-US_TOPIC_0000001145814611__p12459633151811"><strong id="EN-US_TOPIC_0000001145814611__b84235270615047">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778102_abcae9a6ad510442abf53c96ea5d201c5">5min</strong></p>
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</div>
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<div class="section" id="EN-US_TOPIC_0000001145814611__section127431618386"><h4 class="sectiontitle">autovacuum_io_limits</h4><p id="EN-US_TOPIC_0000001145814611__p19802195019459"><strong id="EN-US_TOPIC_0000001145814611__b10864185520181">Parameter description</strong>: Specifies the upper limit of I/Os triggered by the autovacuum process per second.</p>
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<p id="EN-US_TOPIC_0000001145814611__p583341010330"><strong id="EN-US_TOPIC_0000001145814611__b170594016255">Type</strong>: SIGHUP</p>
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<p id="EN-US_TOPIC_0000001145814611__p1980535010454"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778244_en-us_topic_0058967612_b20082249">Value range</strong>: an integer ranging from –1 to 1073741823. <strong id="EN-US_TOPIC_0000001145814611__b11277185015373">–1</strong> indicates that the default Cgroup is used.</p>
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<p id="EN-US_TOPIC_0000001145814611__p1380515503452"><strong id="EN-US_TOPIC_0000001145814611__b1556195535817">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__b18557115513589">–1</strong></p>
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</div>
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<div class="section" id="EN-US_TOPIC_0000001145814611__s33430abba1e849a4b7281648797251ce"><h4 class="sectiontitle">log_autovacuum_min_duration</h4><p id="EN-US_TOPIC_0000001145814611__af86b70c8864a44659e0603178e01b5b3"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778244_en-us_topic_0058967612_b9918227">Parameter description</strong>: Records each step performed by the automatic cleanup process to the server log when the execution time of the automatic cleanup process is greater than or equal to a certain value. This parameter helps track the automatic cleanup behaviors.</p>
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<p id="EN-US_TOPIC_0000001145814611__p6442135693110"><strong id="EN-US_TOPIC_0000001145814611__b29351940122517">Type</strong>: SIGHUP</p>
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<p id="EN-US_TOPIC_0000001145814611__add8dab236fae421a83e666de0d175bb6">For example, set the <strong id="EN-US_TOPIC_0000001145814611__b8585134172512">log_autovacuum_min_duration</strong> parameter to 250 ms to record the information related to the automatic cleanup commands running the parameters whose values are greater than or equal to 250 ms.</p>
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<p id="EN-US_TOPIC_0000001145814611__a07a6fb350c024c5fbef74de5adf6cc60"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778102_a47abd39c97f042919e698a6a149bf0c1">Value range</strong>: an integer ranging from –1 to INT_MAX. The unit is ms.</p>
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<ul id="EN-US_TOPIC_0000001145814611__ude400eafc8654b12893a2f50583f4502"><li id="EN-US_TOPIC_0000001145814611__lb866c09a56e04321abf024b237daa16f">If this parameter is set to <strong id="EN-US_TOPIC_0000001145814611__b842352706143854">0</strong>, all the automatic cleanup operations are recorded in the log.</li><li id="EN-US_TOPIC_0000001145814611__l8f1974416276470f83d403d64a174ee0">If this parameter is set to <strong id="EN-US_TOPIC_0000001145814611__b84235270614415">–1</strong>, all the automatic cleanup operations are not recorded in the log.</li><li id="EN-US_TOPIC_0000001145814611__l46f74849f207472fa5a3c02804eb8f11">If this parameter is not set to <strong id="EN-US_TOPIC_0000001145814611__b842352706144147">–1</strong>, an automatic cleanup operation is skipped and a message is recorded due to lock conflicts.</li></ul>
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<p id="EN-US_TOPIC_0000001145814611__ac40a921ecae342d1a154f631d970bf2e"><strong id="EN-US_TOPIC_0000001145814611__b842352706184820">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__b842352706184824">–1</strong></p>
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</div>
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<div class="section" id="EN-US_TOPIC_0000001145814611__s502d4304994d4da5bd3cda661aab27ac"><a name="EN-US_TOPIC_0000001145814611__s502d4304994d4da5bd3cda661aab27ac"></a><a name="s502d4304994d4da5bd3cda661aab27ac"></a><h4 class="sectiontitle">autovacuum_max_workers</h4><p id="EN-US_TOPIC_0000001145814611__a02743f17d05e49e89826be06b50d977a"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778244_en-us_topic_0058967612_b39331917">Parameter description</strong>: Specifies the maximum number of automatic cleanup threads running at the same time.</p>
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<p id="EN-US_TOPIC_0000001145814611__p1923610101295"><strong id="EN-US_TOPIC_0000001145814611__b117455419258">Type</strong>: POSTMASTER</p>
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<p id="EN-US_TOPIC_0000001145814611__aed697a6422bb4d2b9772a1b00f6e618d"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059777487_en-us_topic_0058967566_b6696864">Value range</strong>: an integer ranging from 0 to 262143. <strong id="EN-US_TOPIC_0000001145814611__b1727104773811">0</strong> indicates that autovacuum is disabled.</p>
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<p id="EN-US_TOPIC_0000001145814611__a0055a0ef82e54f16ab80cf51d5d82146"><strong id="EN-US_TOPIC_0000001145814611__b842352706185015">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__b842352706185018">3</strong></p>
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</div>
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<div class="section" id="EN-US_TOPIC_0000001145814611__s41db964155f3432d8ebe76db75ea50cb"><h4 class="sectiontitle">autovacuum_naptime</h4><p id="EN-US_TOPIC_0000001145814611__abb4867d9d7764a5ba4ed9a2e0d1e6dc8"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778244_en-us_topic_0058967612_b64864880">Parameter description</strong>: Specifies the interval between two automatic cleanup operations.</p>
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<p id="EN-US_TOPIC_0000001145814611__p614254619319"><strong id="EN-US_TOPIC_0000001145814611__b1565212375267">Type</strong>: SIGHUP</p>
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<p id="EN-US_TOPIC_0000001145814611__af4e85e3cf1144a2faaff468b11186d27"><strong id="EN-US_TOPIC_0000001145814611__b16644135514240">Value range</strong>: an integer ranging from 1 to 2147483. The unit is second.</p>
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<p id="EN-US_TOPIC_0000001145814611__afe225e07d4f5493db2d230c4a1cf0562"><strong id="EN-US_TOPIC_0000001145814611__b842352706185119">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778244_b15310055141954">10min</strong></p>
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</div>
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<div class="section" id="EN-US_TOPIC_0000001145814611__s2fba949c06b249f488e37ec0b3a1e8d7"><h4 class="sectiontitle"><strong id="EN-US_TOPIC_0000001145814611__b842352706185129">autovacuum_vacuum_threshold</strong></h4><p id="EN-US_TOPIC_0000001145814611__a0fdbaa013cb048c1b66f771999a6845d"><strong id="EN-US_TOPIC_0000001145814611__b27595912_2">Parameter description</strong>: Specifies the threshold for triggering the <strong id="EN-US_TOPIC_0000001145814611__b142400396734649">VACUUM</strong> operation. When the number of deleted or updated records in a table exceeds the specified threshold, the <strong id="EN-US_TOPIC_0000001145814611__b155649792034649">VACUUM</strong> operation is executed on this table.</p>
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<p id="EN-US_TOPIC_0000001145814611__p3700403312"><strong id="EN-US_TOPIC_0000001145814611__b131721538152615">Type</strong>: SIGHUP</p>
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<p id="EN-US_TOPIC_0000001145814611__a4b35622c9c554230be3c7ec90fbf6451"><strong id="EN-US_TOPIC_0000001145814611__b113836715259">Value range</strong>: an integer ranging from <strong id="EN-US_TOPIC_0000001145814611__b97231818183413">0</strong> to <strong id="EN-US_TOPIC_0000001145814611__b3263122173415">INT_MAX</strong></p>
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<p id="EN-US_TOPIC_0000001145814611__a074ca27bd9e14c92afc20b727d2a43d7"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0058967612_b1551330">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__b84235270616249">50</strong></p>
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</div>
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<div class="section" id="EN-US_TOPIC_0000001145814611__s221c28f820064e7890b242b5ad95c1bd"><h4 class="sectiontitle">autovacuum_analyze_threshold</h4><p id="EN-US_TOPIC_0000001145814611__a6a11767b3e854947bd41d6b08a1077dc"><strong id="EN-US_TOPIC_0000001145814611__b27595912_4">Parameter description</strong>: Specifies the threshold for triggering the <strong id="EN-US_TOPIC_0000001145814611__b46878498534649">ANALYZE</strong> operation. When the number of deleted, inserted, or updated records in a table exceeds the specified threshold, the <strong id="EN-US_TOPIC_0000001145814611__b99369388834649">ANALYZE</strong> operation is executed on this table.</p>
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<p id="EN-US_TOPIC_0000001145814611__p370623203119"><strong id="EN-US_TOPIC_0000001145814611__b16423123812263">Type</strong>: SIGHUP</p>
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<p id="EN-US_TOPIC_0000001145814611__a77cf4fbf33ef488b831c180e2351fec5"><strong id="EN-US_TOPIC_0000001145814611__b707157592">Value range</strong>: an integer ranging from <strong id="EN-US_TOPIC_0000001145814611__b195771730123420">0</strong> to <strong id="EN-US_TOPIC_0000001145814611__b9254173373415">INT_MAX</strong></p>
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<p id="EN-US_TOPIC_0000001145814611__a0b513579dd254e11be781fb3d7b87540"><strong id="EN-US_TOPIC_0000001145814611__b1203493395">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__b1667203459">50</strong></p>
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</div>
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<div class="section" id="EN-US_TOPIC_0000001145814611__sd4638f5991b8491d90d552345ee6c5ec"><h4 class="sectiontitle">autovacuum_vacuum_scale_factor</h4><p id="EN-US_TOPIC_0000001145814611__a5cd30f2e9f764a848306cbbba4f09b45"><strong id="EN-US_TOPIC_0000001145814611__b21399388_1">Parameter description</strong>: Specifies the size scaling factor of a table added to the <strong id="EN-US_TOPIC_0000001145814611__b188598810734649">autovacuum_vacuum_threshold</strong> parameter when a <strong id="EN-US_TOPIC_0000001145814611__b142441122634649">VACUUM</strong> event is triggered.</p>
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<p id="EN-US_TOPIC_0000001145814611__p810818259313"><strong id="EN-US_TOPIC_0000001145814611__b126331138182613">Type</strong>: SIGHUP</p>
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<p id="EN-US_TOPIC_0000001145814611__a52a6cfcfadf348749a639ff428689f9f"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778244_en-us_topic_0058967612_b23973035">Value range</strong>: a floating point number ranging from 0.0 to 100.0</p>
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<p id="EN-US_TOPIC_0000001145814611__adb5e021dd35948b291c230121f148318"><strong id="EN-US_TOPIC_0000001145814611__b60786481_1">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__b84235270610657">0.2</strong></p>
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</div>
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<div class="section" id="EN-US_TOPIC_0000001145814611__s52c6ca5c984e4ac78ec99d2cc2bbda68"><h4 class="sectiontitle">autovacuum_analyze_scale_factor</h4><p id="EN-US_TOPIC_0000001145814611__a42d3b7a643944b4791e1715b16c1d0e0"><strong id="EN-US_TOPIC_0000001145814611__b21399388_4">Parameter description</strong>: Specifies the size scaling factor of a table added to the <strong id="EN-US_TOPIC_0000001145814611__b11831116634649">autovacuum_analyze_threshold</strong> parameter when an <strong id="EN-US_TOPIC_0000001145814611__b160157370634649">ANALYZE</strong> event is triggered.</p>
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<p id="EN-US_TOPIC_0000001145814611__p201751017103117"><strong id="EN-US_TOPIC_0000001145814611__b14808738102618">Type</strong>: SIGHUP</p>
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<p id="EN-US_TOPIC_0000001145814611__a98b82bee8c454e0aa86dbd235bad6f2c"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778244_en-us_topic_0058967612_b28275581">Value range</strong>: a floating point number ranging from 0.0 to 100.0</p>
|
||
<p id="EN-US_TOPIC_0000001145814611__a4b41014dcf414bc8b95ca428de9ce186"><strong id="EN-US_TOPIC_0000001145814611__b60786481_3">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__b8423527061077">0.1</strong></p>
|
||
</div>
|
||
<div class="section" id="EN-US_TOPIC_0000001145814611__s60e0fbc2967c44b3bb6c53c29e9c772e"><h4 class="sectiontitle">autovacuum_freeze_max_age</h4><p id="EN-US_TOPIC_0000001145814611__a378c10d2879740ebbc4d0af3d2b16a06"><strong id="EN-US_TOPIC_0000001145814611__b47690497">Parameter description</strong>: Specifies the maximum age (in transactions) that a table's <strong id="EN-US_TOPIC_0000001145814611__b2581408191">pg_class.relfrozenxid</strong> column can attain before a VACUUM operation is forced to prevent transaction ID wraparound within the table. </p>
|
||
<p id="EN-US_TOPIC_0000001145814611__p4799185915408">The old files under the subdirectory of <strong id="EN-US_TOPIC_0000001145814611__b02179223265">pg_clog/</strong> can also be deleted by the VACUUM operation. Even if the automatic cleanup process is forbidden, the system will invoke the automatic cleanup process to prevent the cyclic repetition.</p>
|
||
<p id="EN-US_TOPIC_0000001145814611__p173051033183017"><strong id="EN-US_TOPIC_0000001145814611__b1198163872615">Type</strong>: POSTMASTER</p>
|
||
<p id="EN-US_TOPIC_0000001145814611__a8f62dcc043de4c81ba2ee70b16555c70"><strong id="EN-US_TOPIC_0000001145814611__b192225161317">Value range</strong>: an integer ranging from 100000 to 576460752303423487</p>
|
||
<p id="EN-US_TOPIC_0000001145814611__a99092a1b31824e1ca4fd671644763d90"><strong id="EN-US_TOPIC_0000001145814611__b1887492023910">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__b1687582083913">20000000000</strong></p>
|
||
</div>
|
||
<div class="section" id="EN-US_TOPIC_0000001145814611__sd3082605f4ef4a4383807a078c38bc1e"><h4 class="sectiontitle">autovacuum_vacuum_cost_delay</h4><p id="EN-US_TOPIC_0000001145814611__aa9e29e9224b243758df82ae2606aab5e"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778244_en-us_topic_0058967612_b39055335">Parameter description</strong>: Specifies the value of the cost delay used in the autovacuum operation.</p>
|
||
<p id="EN-US_TOPIC_0000001145814611__p62421778312"><strong id="EN-US_TOPIC_0000001145814611__b71411939152618">Type</strong>: SIGHUP</p>
|
||
<p id="EN-US_TOPIC_0000001145814611__ac28c2d20ef894e2e9c8517e5a942abce"><strong id="EN-US_TOPIC_0000001145814611__en-us_topic_0059778244_en-us_topic_0058967612_b21083041">Value range</strong>: an integer ranging from –1 to 100. The unit is ms. <strong id="EN-US_TOPIC_0000001145814611__b185331434133917">-1</strong> indicates that the normal vacuum cost delay is used.</p>
|
||
<p id="EN-US_TOPIC_0000001145814611__af37beecf08954cfcaa966bedcf008dbd"><strong id="EN-US_TOPIC_0000001145814611__b189481635144016">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__b895053544011">20ms</strong></p>
|
||
</div>
|
||
<div class="section" id="EN-US_TOPIC_0000001145814611__s0813cb847c624c68af2c910e1cb1b7f9"><h4 class="sectiontitle">autovacuum_vacuum_cost_limit</h4><p id="EN-US_TOPIC_0000001145814611__abd05f61046554cbba319c60e10b0eaef"><strong id="EN-US_TOPIC_0000001145814611__b39055335_4">Parameter description</strong>: Specifies the value of the cost limit used in the autovacuum operation.</p>
|
||
<p id="EN-US_TOPIC_0000001145814611__p1134113462309"><strong id="EN-US_TOPIC_0000001145814611__b2310143920261">Type</strong>: SIGHUP</p>
|
||
<p id="EN-US_TOPIC_0000001145814611__aa85295cf591b496fba57f09ab1475ac1"><strong id="EN-US_TOPIC_0000001145814611__b453771993">Value range</strong>: an integer ranging from –1 to 10000. <strong id="EN-US_TOPIC_0000001145814611__b6332122119415">-1</strong> indicates that the normal vacuum cost limit is used.</p>
|
||
<p id="EN-US_TOPIC_0000001145814611__a6cf0563044774291ad5ac769f3853455"><strong id="EN-US_TOPIC_0000001145814611__b53628433514291">Default value</strong>: <strong id="EN-US_TOPIC_0000001145814611__b164450946414291">–1</strong></p>
|
||
</div>
|
||
</div>
|
||
<div>
|
||
<div class="familylinks">
|
||
<div class="parentlink"><strong>Parent topic:</strong> <a href="dws_04_0883.html">GUC Parameters</a></div>
|
||
</div>
|
||
</div>
|
||
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