From: Dan Nelson
Date: June 25 2006 7:01pm
Subject: Re: A lot of HD Writing
List-Archive: http://lists.mysql.com/mysql/199295
Message-Id: <20060625190117.GD83209@dan.emsphone.com>
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In the last episode (Jun 24), Santiago del Castillo said:
> Hi, is usual to have a lot of HD writing on a MySQL server where
> (according to mytop) there are between 800 and 1200 queries per
> second? my MRTG is showing a lot of HD Writing and i wanted to know
> if it's usual. The database is growing about 11 MB every 3 minutes.

If you are issuing INSERT or UPDATE queries, you should expect disk
writes :)
 
> An extra question:
> Which scale of MaxBytes should i use for my HD Writing MRTG config? i'm
> using "MaxBytes[hd-write]: 2400" right now. The Disk is a 80 GB SCSI disc
> with RAID 1

What units is hd-write in?  If you're graphing the net-snmp diskIOTable
values (diskIONRead and diskIONWritten or the preferred 64-bit
counterparts diskIONReadX and diskIONWrittenX), they are in bytes.

2400 sounds either way too low if your units are KB/sec (==2.4 MB/sec),
or way too high if it's in MB/sec (==2.4 GB/sec).

-- 
	Dan Nelson
	dnelson@stripped