From: Tomasz Chmielewski <tch@virtall.com>
To: Calvin Walton <calvin.walton@kepstin.ca>
Cc: "linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>
Subject: Re: RAID-1 - suboptimal write performance?
Date: Fri, 16 May 2014 21:41:35 +0100 [thread overview]
Message-ID: <20140516214135.23fefc39@s9> (raw)
In-Reply-To: <1400263584.979.17.camel@sasami.ottawa.blindsidenetworks.com>
On Fri, 16 May 2014 14:06:24 -0400
Calvin Walton <calvin.walton@kepstin.ca> wrote:
> No comment on the performance issue, other than to say that I've seen
> similar on RAID-10 before, I think.
>
> > Also, what happens when the system crashes, and one drive has
> > several hundred megabytes data more than the other one?
>
> This shouldn't be an issue as long as you occasionally run a scrub or
> balance. The scrub should find it and fix the missing data, and a
> balance would just rewrite it as proper RAID-1 as a matter of course.
It's similar (writes to just one drive, while the other is idle) when
removing (many) snapshots.
Not sure if that's optimal behaviour.
--
Tomasz Chmielewski
http://wpkg.org
next prev parent reply other threads:[~2014-05-16 20:41 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-16 15:48 RAID-1 - suboptimal write performance? Tomasz Chmielewski
2014-05-16 18:06 ` Calvin Walton
2014-05-16 20:41 ` Tomasz Chmielewski [this message]
2014-05-16 21:36 ` Austin S Hemmelgarn
2014-05-18 18:49 ` Brendan Hide
2014-05-23 12:57 ` Roman Mamedov
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