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From: Keith Mannthey <kmannth@us.ibm.com>
To: "linux-ext4@vger.kernel.org" <linux-ext4@vger.kernel.org>
Subject: Barriers per second while doing Odirect Random Writes
Date: Mon, 26 Apr 2010 00:06:17 -0700	[thread overview]
Message-ID: <1272265577.9664.57.camel@keith-laptop> (raw)

Ted and all, 
  While using this FFSB test profile:
http://btrfs.boxacle.net/repository/raid/2010-04-14_2004//ext4-2.6.34-rc3-nobarrier//btrfs1.ffsb.random_writes_odirect__threads_0128.10-04-21_17.38.39/benchmark/profile
(The profile is 128 threads of all odirect random writes. )
on my raid box I am seeing (via Darricks block_barrier tracepoint) right
about 32 barriers per second.

Initial analysis using perf shows kdmflush as the cause. I will continue
to look into this.  

Thanks,
  Keith Mannthey
  LTC FS-Dev 




                 reply	other threads:[~2010-04-26  7:06 UTC|newest]

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