Date: Mon, 10 Jan 2005 03:23:30 +0200
From: Sami Farin <7atbggg02@sneakemail.com>
To: linux-kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: vfat unlink latency 54.6ms for 128MB files
Message-ID: <20050110012330.GA10846@m.safari.iki.fi>
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Just wondering, when I remove a 128MB file on vfat partition
(usb-storage, memcard reader), it causes 54.6ms latency
in rtc_latencytest...  latency seems to increase linearly
as the filesize grows.  I calculated 1s would be reached with
2344MB file but I didn't bother trying that yet.
Are there any possible fixes for fat fs so
that it doesn't disable interrupts for that long a time?

When I use loop device (the file on reiserfs), I get 45.9ms latency,
so this is not usb's fault. 

These with Linux-2.6.10-ac8 on UP, PPro+, no preempt.
http://safari.iki.fi/vfat-unlink/

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