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To: Poul-Henning Kamp <phk@critter.tfs.com>
cc: current@freebsd.org
In-reply-to: Your message of "Tue, 14 Nov 95 09:33:11 +0100."
             <252.816337991@critter.tfs.com> 
From: David Greenman <davidg@Root.COM>
Reply-To: davidg@Root.COM
Date: Tue, 14 Nov 1995 00:43:12 -0800
Sender: owner-current@freebsd.org
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>> "Fixing" this is very difficult and would require a rewrite of the code
>> involved.
>
>Why would this:
>
>	void
>	update_every_3_sec()
>	{
>		static int i;
>
>		for all buffers {
>			if ((blockno % 10) == i)
>				write it
>		}
>		i = ++i % 10;
>	}
>
>give more io traffic ?

   Because delayed write buffers are delayed for a reason. It's the
expectation that additional data/changes will be made to the buffer before
it is written out. In the case where stuff is being appended to files via
small writes (like log files, for instance), doing an update 10 times more
often may very well increase the number of writes by 10 times.

-DG