Subject: Re: [HACKERS] PostgreSQL, NetBSD and NFS
To: D'Arcy J.M. Cain <firstname.lastname@example.org>
From: Tom Lane <email@example.com>
Date: 02/05/2003 15:09:09
"D'Arcy J.M. Cain" <firstname.lastname@example.org> writes:
> On Wednesday 05 February 2003 13:04, Ian Fry wrote:
>> How about adjusting the read and write-size used by the NetBSD machine? I
>> think the default is 32k for both read and write on i386 machines now.
>> Perhaps try setting them back to 8k (it's the -r and -w flags to mount_nfs,
> Hey! That did it.
> So, why does this fix it?
I think now you file a bug report with the NetBSD kernel folk. My
thoughts are running in the direction of a bug having to do with
scattering a 32K read into multiple kernel disk-cache buffers or
gathering together multiple cache buffer contents to form a 32K write.
Unless NetBSD has changed from its heritage, the kernel disk cache
buffers are 8K, and so an 8K NFS read or write would never cross a
cache buffer boundary. But 32K would.
Or it could be a similar bug on the NFS server's side?
regards, tom lane