Horton

Re: Re[2]: Allowing WAL fsync to be done via O_SYNC

Bruce Momjian <pgman@candle.pha.pa.us>

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From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Alfred Perlstein <bright@wintelcom.net>
Cc: Xu Yifeng <jamexu@telekbird.com.cn>, Tom Lane <tgl@sss.pgh.pa.us>, "Mikheev, Vadim" <vmikheev@SECTORBASE.COM>, Peter Eisentraut <peter_e@gmx.net>, pgsql-hackers@postgresql.org
Date: 2001-03-16T15:11:30Z
Lists: pgsql-hackers 
> > Could anyone consider fork a syncer process to sync data to disk ?
> > build a shared sync queue, when a daemon process want to do sync after
> > write() is called, just put a sync request to the queue. this can release
> > process from blocked on writing as soon as possible. multipile sync
> > request for one file can be merged when the request is been inserting to
> > the queue.
> 
> I suggested this about a year ago. :)
> 
> The problem is that you need that process to potentially open and close
> many files over and over.
> 
> I still think it's somewhat of a good idea.

I like the idea too, but people want the transaction to return COMMIT
only after data has been fsync'ed so I don't see a big win.

-- 
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