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Date: Thu, 25 Jul 2013 08:36:04 -0600
From: Jens Axboe <axboe@kernel.dk>
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Subject: Re: Weird trim test results
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To: Matthew Eaton <m.eaton82@gmail.com>
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On 07/24/2013 02:22 PM, Matthew Eaton wrote:
> Hi guys,
> 
> I'm using this simple trim test on a raw SSD but getting very low
> performance.  Bandwidth seems to be tied to the block size.  Am I
> doing something wrong?

What kernel are you on? This looks like a missing unplug issue. If you
run a blktrace for a few seconds while the test is ongoing, the output
of blkparse should reveal if you are seeing timer unplugs.

-- 
Jens Axboe