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@ -729,7 +729,7 @@ |
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<acronym>GIN</> is capable of postponing much of this work by inserting |
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new tuples into a temporary, unsorted list of pending entries. |
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When the table is vacuumed, or if the pending list becomes larger than |
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<xref linkend="guc-pending-list-cleanup-size">, the entries are moved to the |
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<xref linkend="guc-gin-pending-list-limit">, the entries are moved to the |
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main <acronym>GIN</acronym> data structure using the same bulk insert |
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techniques used during initial index creation. This greatly improves |
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<acronym>GIN</acronym> index update speed, even counting the additional |
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@ -812,22 +812,22 @@ |
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</varlistentry> |
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<varlistentry> |
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<term><xref linkend="guc-pending-list-cleanup-size"></term> |
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<term><xref linkend="guc-gin-pending-list-limit"></term> |
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<listitem> |
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<para> |
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During a series of insertions into an existing <acronym>GIN</acronym> |
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index that has <literal>fastupdate</> enabled, the system will clean up |
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the pending-entry list whenever the list grows larger than |
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<varname>pending_list_cleanup_size</>. To avoid fluctuations in observed |
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<varname>gin_pending_list_limit</>. To avoid fluctuations in observed |
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response time, it's desirable to have pending-list cleanup occur in the |
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background (i.e., via autovacuum). Foreground cleanup operations |
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can be avoided by increasing <varname>pending_list_cleanup_size</> |
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can be avoided by increasing <varname>gin_pending_list_limit</> |
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or making autovacuum more aggressive. |
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However, enlarging the threshold of the cleanup operation means that |
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if a foreground cleanup does occur, it will take even longer. |
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</para> |
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<para> |
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<varname>pending_list_cleanup_size</> can be overridden for individual |
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<varname>gin_pending_list_limit</> can be overridden for individual |
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GIN indexes by changing storage parameters, and which allows each |
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GIN index to have its own cleanup threshold. |
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For example, it's possible to increase the threshold only for the GIN |
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