Re: Load distributed checkpoint

From: Martijn van Oosterhout <kleptog(at)svana(dot)org>
To: Takayuki Tsunakawa <tsunakawa(dot)takay(at)jp(dot)fujitsu(dot)com>
Cc: ITAGAKI Takahiro <itagaki(dot)takahiro(at)oss(dot)ntt(dot)co(dot)jp>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: Load distributed checkpoint
Date: 2006-12-20 11:17:05
Message-ID: 20061220111705.GB12639@svana.org
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers pgsql-patches

On Wed, Dec 20, 2006 at 08:10:56PM +0900, Takayuki Tsunakawa wrote:
> One question is the disk utilization. While bgwriter is fsync()ing,
> %util of WAL disk drops to almost 0. But the the bandwidth of
> Ultra320 SCSI does not appear to be used fully. Any idea?

That implies that fsyncing a datafile blocks fsyncing the WAL. That
seems terribly unlikely (although...). What OS/Kernel/Filesystem is
this. I note a sync bug in linux for ext3 that may have relevence.

Have a nice day,

--
Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
> From each according to his ability. To each according to his ability to litigate.

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Russell Smith 2006-12-20 11:33:53 Re: column ordering, was Re: [PATCHES] Enums patch v2
Previous Message Takayuki Tsunakawa 2006-12-20 11:10:56 Re: Load distributed checkpoint

Browse pgsql-patches by date

  From Date Subject
Next Message Russell Smith 2006-12-20 11:33:53 Re: column ordering, was Re: [PATCHES] Enums patch v2
Previous Message Takayuki Tsunakawa 2006-12-20 11:10:56 Re: Load distributed checkpoint