Re: RE: [COMMITTERS] pgsql/src/backend/access/transam ( xact.c xlog.c) - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: RE: [COMMITTERS] pgsql/src/backend/access/transam ( xact.c xlog.c)
Date
Msg-id 200011160531.AAA27796@candle.pha.pa.us
Whole thread Raw
In response to RE: RE: [COMMITTERS] pgsql/src/backend/access/transam ( xact.c xlog.c)  ("Mikheev, Vadim" <vmikheev@SECTORBASE.COM>)
List pgsql-hackers
[ Charset ISO-8859-1 unsupported, converting... ]
> > Earlier, Vadim was talking about arranging to share fsyncs of the WAL
> > log file across transactions (after writing your commit record to the
> > log, sleep a few milliseconds to see if anyone else fsyncs before you
> > do; if not, issue the fsync yourself).  That would offer less-than-
> > one-fsync-per-transaction performance without giving up any 
> > guarantees.
> > If people feel a compulsion to have a tunable parameter, let 'em tune
> > the length of the pre-fsync sleep ...
> 
> Already implemented (without ability to tune this parameter - 
> xact.c:CommitDelay, - yet). Currently CommitDelay is 5, so
> backend sleeps 1/200 sec before checking/forcing log fsync.

But it returns _completed_ to the client before sleeping, right?

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