From owner-freebsd-hackers  Wed Jan 16 14:30:19 2002
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Date: Wed, 16 Jan 2002 22:29:39 +0000
From: David Malone <dwmalone@walton.maths.tcd.ie>
To: Josef Grosch <jgrosch@mooseriver.com>
Cc: hackers@freebsd.org
Subject: Re: [nicole@unixgirl.com: What is biord?]
Message-ID: <20020116222939.GA81401@walton.maths.tcd.ie>
References: <20020116141825.A45998@mooseriver.com>
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On Wed, Jan 16, 2002 at 02:18:25PM -0800, Josef Grosch wrote:
>  I have a mysql database that seems slow and when looking at it in top it
> always seems to be in a state of biord
>  What the heck is biord I can't find this anywere

22:21:gonzo 3% fgrep biord /usr/src/sys/kern/*
/usr/src/sys/kern/vfs_bio.c:            tsleep(&bp->b_xflags, PRIBIO, "biord", 0);
/usr/src/sys/kern/vfs_bio.c:                    tsleep(bp, PRIBIO, "biord", 0);

If you have a look at the code, in vfs_bio.c around these lines,
you'll see it is to do with waiting for buffers to be read or
written. Basically it means that the database is spending alot
of its time waiting for the disk to catch up.

	David.

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