linux-kernel - Re: [patch v2 2/6] blk: dont allow discard request merge temporarily

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20120322062850.GA25288@infradead.org>
Date:	Thu, 22 Mar 2012 02:28:51 -0400
From:	Christoph Hellwig <hch@...radead.org>
To:	"Martin K. Petersen" <martin.petersen@...cle.com>
Cc:	Shaohua Li <shli@...nel.org>, Vivek Goyal <vgoyal@...hat.com>,
	linux-kernel@...r.kernel.org, linux-raid@...r.kernel.org,
	neilb@...e.de, axboe@...nel.dk
Subject: Re: [patch v2 2/6] blk: dont allow discard request merge temporarily

On Wed, Mar 21, 2012 at 10:18:54PM -0400, Martin K. Petersen wrote:
> >>>>> "Shaohua" == Shaohua Li <shli@...nel.org> writes:
> 
> Shaohua> Enabling discard merge is required for device with slow discard
> Shaohua> (and very helpful for raid),
> 
> Before RAID support there really wasn't much point. That's one of the
> reasons the current discard merge code has survived despite being
> completely broken.

I've actually send repeated bug reports about it beeing broken when
I enabled async discard in XFS which led to merges, and debugged it down
to beeing a problem with merges.  But Jens didn't like my patch to mark
them nomerged, so we still couldn't commit the async discard support for
XFS which would have helped quite a bit with discard performance.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/