From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dave Pitts <dpitts@cozx.com>
Subject: dm-cache warming
Date: Fri, 26 Jul 2013 09:24:16 -0600
Message-ID: <51F294A0.6080103@cozx.com>
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Hello:

I've been trying to do some performance testing for a client and can't seem to 
get the dm-cache warmed. The values displayed in the "dmsetup status" command 
seem too low. I've been trying to use the "raw" devices setup for the cache and 
NOT use a file system or database. I've tried sequential writes/reads to the 
devices (ie. dd ) and dividing up the space to be tested and do I/O over a 
number of segments to try to break any sequential I/O tests. Any ideas as to 
what I may doing wrong? Do I need to randomize the I/O?

System: RHEL 7.0 Alpha3, 3.9.7 kernel

Thanks in advance..

-- 
Dave Pitts             PULLMAN: Travel and sleep in safety and comfort.
dpitts@cozx.com