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To: Don Lewis <truckman@FreeBSD.org>
Subject: Re: access to hard drives is "blocked" by writes to a flash drive
In-reply-to: <201303050840.r258egAG012697@gw.catspoiler.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
References: <201303050840.r258egAG012697@gw.catspoiler.org>
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Date: Tue, 05 Mar 2013 08:45:08 +0000
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In message <201303050840.r258egAG012697@gw.catspoiler.org>, Don Lewis writes:

>For composite devices such as mirrors, using the first underlying device
>is probably a reasonable choice.  For more complicated cases, or to
>override the default, the syncer thread could be specified as a mount
>option.

I doubt that will be any better than what we have today.

I think it is a much better idea to have the syncer monitor bio write
latency and adjust accordingly.


-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.