| From: | Teodor Sigaev <teodor(at)sigaev(dot)ru> |
|---|---|
| To: | Anastasia Lubennikova <a(dot)lubennikova(at)postgrespro(dot)ru>, Andres Freund <andres(at)anarazel(dot)de> |
| Cc: | Alexander Korotkov <a(dot)korotkov(at)postgrespro(dot)ru>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: [PATCH] Microvacuum for gist. |
| Date: | 2015-09-04 12:11:12 |
| Message-ID: | 55E98A60.3000805@sigaev.ru |
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| Thread: | |
| Lists: | pgsql-hackers |
Some notices
1 gistvacuumpage():
OffsetNumber deletable[MaxOffsetNumber];
Seems, MaxOffsetNumber is too much, MaxIndexTuplesPerPage is enough
2 Loop in gistkillitems() for searching heap pointer. It seems to me that
it could be a performance problem. To fix it, it's needed to remember index
tuple's offset number somewhere near GISTScanOpaqueData->killedItems. And
gistkillitems() will loop over offsets and compare heap pointer from killedItems
and index tuple, if they doesn't match then just skip this index tuple.
3 Connected with previous, could you show some performance tests?
--
Teodor Sigaev E-mail: teodor(at)sigaev(dot)ru
WWW: http://www.sigaev.ru/
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