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From: Alireza Haghdoost <alireza@cs.umn.edu>
To: Linux RAID <linux-raid@vger.kernel.org>
Cc: Neil Brown <neilb@suse.de>
Subject: Inject I/O latency for RAID5/6 read and writes
Date: Mon, 23 Feb 2015 12:32:47 -0600	[thread overview]
Message-ID: <CAB-428=gcsgxa1k83h0QWmijhe_kXaLMQZqs+m=Zb0OWX06geA@mail.gmail.com> (raw)

I needed to inject I/O completion latency in the RAID5/6 codes for
test purpose. I was wondering where would be the good place in
md/raid5.c code to add delay ?

So far I have tried adding mdelay/udelay in raid5_end_write_request()
and it seems it works to increase I/O completion of writes. However,
adding delay in raid5_end_read_request() does not really change the
read I/O latency. Any idea ?

--Alireza

             reply	other threads:[~2015-02-23 18:32 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-02-23 18:32 Alireza Haghdoost [this message]
2015-03-12 21:31 ` Inject I/O latency for RAID5/6 read and writes Alireza Haghdoost
2015-03-13 10:29   ` Sebastian Parschauer

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