From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alasdair G Kergon <agk@redhat.com>
Subject: Re: [PATCH 05/24] dm cache policy mq:
	implement	writeback_work() and mq_{set, clear}_dirty()
Date: Fri, 25 Oct 2013 17:06:12 +0100
Message-ID: <20131025160612.GG17070@agk-dp.fab.redhat.com>
References: <1382639437-27007-1-git-send-email-snitzer@redhat.com>
	<1382639437-27007-6-git-send-email-snitzer@redhat.com>
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To: Mike Snitzer <snitzer@redhat.com>
Cc: Morgan Mears <morgan.mears@netapp.com>, Heinz Mauelshagen <heinzm@redhat.com>, dm-devel@redhat.com, Joe Thornber <ejt@redhat.com>
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On Thu, Oct 24, 2013 at 02:30:18PM -0400, Mike Snitzer wrote:
> From: Joe Thornber <ejt@redhat.com>
 
> --- a/drivers/md/dm-cache-policy-mq.c

> -	 * We maintain two queues of entries.  The cache proper contains

> +	 * We maintain three queues of entries.  The cache proper,

Does the Documentation file need updating too?

: The multiqueue policy has two sets of 16 queues: one set for entries
: waiting for the cache and another one for those in the cache.

> @@ -580,7 +585,16 @@ static void check_generation(struct mq_policy *mq)

Is the comment about this function no longer accurate?

: * At the moment the threshold is taken by averaging the hit counts of some
: * of the entries in the cache (the first 20 entries of the first level).

- It looks at clean before dirty?
- It looks at more than just the first level if it needs to?

> +// FIXME: can __mq_set_clear_dirty block?

Still to check this before inclusion upstream?

Alasdair