| From: | Simon Riggs <simon(at)2ndQuadrant(dot)com> |
|---|---|
| To: | pgsql-hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | WALInsertLock tuning |
| Date: | 2011-06-06 16:15:28 |
| Message-ID: | BANLkTingB35r5Z3TDD5B2sajSbmB3sgAWg@mail.gmail.com |
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| Lists: | pgsql-hackers |
In earlier discussions of how to improve WALInsertLock contention, it
was observed that we must zero each new page before we advance the WAL
insertion point.
http://postgresql.1045698.n5.nabble.com/Reworking-WAL-locking-td1983647.html
IMHO the page zeroing is completely unnecessary, and replication works
perfectly well without that (as a test of recovery logic). It is
unnecessary because we already allow non-zeroed parts of WAL files,
and provide a mechanism to detect stale data.
The following trivial patch removes the page zeroing, which reduces
the lock duration.
Comments?
--
Simon Riggs http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services
| Attachment | Content-Type | Size |
|---|---|---|
| walinsertlock_avoid_zero.v1.patch | application/octet-stream | 1.4 KB |
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