From: | Zeugswetter Andreas SB <ZeugswetterA(at)wien(dot)spardat(dot)at> |
---|---|
To: | "'Tom Lane'" <tgl(at)sss(dot)pgh(dot)pa(dot)us>, "Mikheev, Vadim" <vmikheev(at)SECTORBASE(dot)COM> |
Cc: | pgsql-hackers(at)postgresql(dot)org |
Subject: | AW: WAL does not recover gracefully from out-of-disk-sp ace |
Date: | 2001-03-09 09:28:14 |
Message-ID: | 11C1E6749A55D411A9670001FA687963368236@sdexcsrv1.f000.d0188.sd.spardat.at |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
> > Even with true fdatasync it's not obviously good for performance - it takes
> > too long time to write 16Mb files and fills OS buffer cache with trash-:(
>
> True. But at least the write is (hopefully) being done at a
> non-performance-critical time.
So you have non critical time every five minutes ?
Those platforms that don't have fdatasync won't profit anyway.
Even if the IO is done by postmaster the write to the disk has a severe
impact on concurrent other disk activity.
In a real 5 minutes checkpoint setup we are seriously talking about
48 Mb at least, or you risc foreground log creation. On systems I know,
that means 100% busying the disk for at least 8 seconds.
Andreas
From | Date | Subject | |
---|---|---|---|
Next Message | Tatsuo Ishii | 2001-03-09 11:42:26 | Re: Internationalized error messages |
Previous Message | Karel Zak | 2001-03-09 07:53:20 | Re: Internationalized error messages |