xfs
[Top] [All Lists]

Re: XFS IO multiplication problem on centos/rhel 6 using hp p420i raid c

To: Dennis Kaarsemaker <dennis.kaarsemaker@xxxxxxxxxxx>
Subject: Re: XFS IO multiplication problem on centos/rhel 6 using hp p420i raid controllers
From: Stan Hoeppner <stan@xxxxxxxxxxxxxxxxx>
Date: Thu, 07 Mar 2013 07:10:47 -0600
Cc: Dave Chinner <david@xxxxxxxxxxxxx>, xfs@xxxxxxxxxxx
Delivered-to: xfs@xxxxxxxxxxx
In-reply-to: <1362651128.16657.13.camel@seahawk>
References: <1362060736.1247.30.camel@seahawk> <20130228194023.GQ5551@dastard> <1362577992.1247.84.camel@seahawk> <20130307035737.GC6369@dastard> <1362651128.16657.13.camel@seahawk>
Reply-to: stan@xxxxxxxxxxxxxxxxx
User-agent: Mozilla/5.0 (Windows NT 5.1; rv:17.0) Gecko/20130215 Thunderbird/17.0.3
On 3/7/2013 4:12 AM, Dennis Kaarsemaker wrote:

> I see, so now I need to find out what's causing the larger average
> request size. Would you happen to know a list of common causes?

Given that mysql is doing the writes, that's the first place to look.
Is the mysql version the same on all machines?  If not, what changed
between versions?  How about the config?  How about the sql code driving
the IO, is it the same?  Is this host using a different mysql log or db
file format?  Is the logging method the same?  Is it writing the same
total amount of data to the filesystem, but just in larger chunks?  Etc,
etc.

-- 
Stan

<Prev in Thread] Current Thread [Next in Thread>