xfs
[Top] [All Lists]

Re: quotacheck speed

To: Dave Chinner <david@xxxxxxxxxxxxx>
Subject: Re: quotacheck speed
From: Arkadiusz Miśkiewicz <arekm@xxxxxxxx>
Date: Tue, 14 Feb 2012 06:35:45 +0100
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>, xfs@xxxxxxxxxxx
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=maven.pl; s=maven; h=from:to:subject:date:user-agent:cc:references:in-reply-to :mime-version:content-type:content-transfer-encoding:message-id; bh=oYsNTRZdLx+T/ALNjtwfsFc0vHatMpC4tp+w875Gc6M=; b=opgLDmOOKPbE3lqoNpz4PFTluXrCNPmEqWnlAhH1tcmu4rZK24K/OLWkFJ3n4ZWeC3 qAlw51whky6be3a3W7Bi3S4Z8hGWjY80wTYcvzkyh2WKVxE/63qX0L9h6P1nxieZt4kw 8EWjxibUCGh6fwMyBp/4otXH9+CpIPxoKQviY=
In-reply-to: <20120213234235.GE14132@dastard>
References: <201202122201.07649.arekm@xxxxxxxx> <201202131909.50605.arekm@xxxxxxxx> <20120213234235.GE14132@dastard>
User-agent: KMail/1.13.7 (Linux/3.3.0-rc3-00171-g8df54d6-dirty; KDE/4.8.0; x86_64; ; )
On Tuesday 14 of February 2012, Dave Chinner wrote:
> On Mon, Feb 13, 2012 at 07:09:50PM +0100, Arkadiusz Miśkiewicz wrote:
> > On Monday 13 of February 2012, Christoph Hellwig wrote:
> > > On Sun, Feb 12, 2012 at 10:01:07PM +0100, Arkadiusz Mi??kiewicz wrote:
> > > > Hi,
> > > > 
> > > > When mounting 800GB filesystem (after repair for example) here
> > > > quotacheck takes 10 minutes. Quite long time that adds to whole time
> > > > of filesystem downtime (repair + quotacheck).
> > > > 
> > > > I wonder if quotacheck can be somehow improved or done differently
> > > > like doing it in parallel with normal fs usage (so there will be no
> > > > downtime) ?
> > > 
> > > I think the best idea to improve the performance in case you did a
> > > repair is to integrate the quotacheck code into repair.  It's fairly
> > > simple given that quotacheck simply walks all inodes and adds their
> > > space usage to the correct user/group/project, and given that repair
> > > already walks all inodes, and checks their block maps it does most of
> > > that work already.
> > 
> > That would be interesting and probably make
> > 
> > > The only downside would be that the memory usage
> > > of repair increases a bit by keeping the dquots in memoryb, but even
> > > for your 130000 dquot setup that would add about 100 bytes * 130000
> > > please a bit of in-memory metadata (less than 20MB total) of memory
> > > usage, so it probably is a good tradeoff.
> > > 
> > > 
> > > In what cases do you regularly run quotacheck when you did not do
> > > a repair first?
> > 
> > I don't initiate quotacheck manually. AFAIK internal xfs quotacheck
> > happens in two cases here:
> > 1) repair->mount
> > 2) filesystem has quotacheck done properly some time ago -> umount ->
> > mount-
> > 
> > >oops/reset/something like that happens while mounting -> new mount
> 
> So you'd like both quotacheck to be sped up and repair
> to do it as well? ;)

Well, 1) is happening much more often than 2) :-)

-- 
Arkadiusz Miśkiewicz        PLD/Linux Team
arekm / maven.pl            http://ftp.pld-linux.org/

<Prev in Thread] Current Thread [Next in Thread>