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From: Larkin Lowrey <llowrey@nuclearwinter.com>
To: Rolf Fokkens <rolf@rolffokkens.nl>, linux-bcache@vger.kernel.org
Subject: Re: Read cache contents cleared on boot?
Date: Tue, 10 Dec 2013 17:25:35 -0600	[thread overview]
Message-ID: <52A7A2EF.8020507@nuclearwinter.com> (raw)
In-Reply-To: <52A4BB32.9010104@rolffokkens.nl>

On 12/8/2013 12:32 PM, Rolf Fokkens wrote:
> On 11/06/2013 11:08 PM, Larkin Lowrey wrote:
>> When I boot my cache usage returns to 1.3GB even when it was nearly full
>> at shutdown (as reported by bcache-status). Are the read cache contents
>> not retained across a reboot?
> Same here: After running for a while bcache-status reports a Total
> Cache Used of 2.1GB. After reboot it's back to 910MB all the time. Did
> you get an explanation for this?

I never got an explanation but I have a theory. My cache has started
booting with much more total cache used reported. My theory is that
garbage collection is occurring on boot and that my pre-shutdown numbers
contain a lot of dirty pages. I plan to verify this, when I get a
chance, by forcing a garbage collection before shutdown and comparing
the post GC numbers to the post boot numbers.

--Larkin

      reply	other threads:[~2013-12-10 23:25 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-11-06 22:08 Read cache contents cleared on boot? Larkin Lowrey
2013-12-08 18:32 ` Rolf Fokkens
2013-12-10 23:25   ` Larkin Lowrey [this message]

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