linux-kernel - Re: [patch] mm/vmalloc: remove block allocation bitmap

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]

Date:	Wed, 20 Apr 2011 12:39:54 -0400
From:	Christoph Hellwig <hch@...radead.org>
To:	Mel Gorman <mel@....ul.ie>
Cc:	Johannes Weiner <hannes@...xchg.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Nick Piggin <npiggin@...nel.dk>,
	Hugh Dickins <hughd@...gle.com>, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org
Subject: Re: [patch] mm/vmalloc: remove block allocation bitmap

On Wed, Apr 20, 2011 at 10:46:47AM +0100, Mel Gorman wrote:
> It'd be interesting but for the purposes of this patch I think it
> would be more useful to see the results of some benchmark that is vmap
> intensive. Something directory intensive running on XFS should do the
> job just to confirm no regression, right? A profile might indicate
> how often we end up scanning the full list, finding it dirty and
> calling new_vmap_block but even if something odd showed up there,
> it would be a new patch.

Note that the default mkfs.xfs options will not trigger any vmap
calls at runtime.  You'll need a filesystem with a large directory
block size to trigger heavy vmap usage.

--
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/