linux-ext4 - Re: [PATCH -V3 04/11] ext4: Add percpu dirty block accounting.

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] [day] [month] [year] [list]

Message-id: <20081011211007.GB2009@webber.adilger.int>
Date:	Sat, 11 Oct 2008 15:10:07 -0600
From:	Andreas Dilger <adilger@....com>
To:	Eric Sandeen <sandeen@...hat.com>
Cc:	"Aneesh Kumar K.V" <aneesh.kumar@...ux.vnet.ibm.com>,
	cmm@...ibm.com, tytso@....edu, linux-ext4@...r.kernel.org,
	Alex Zhuravlev <Alex.Zhuravlev@....com>
Subject: Re: [PATCH -V3 04/11] ext4: Add percpu dirty block accounting.

On Oct 09, 2008  15:44 -0500, Eric Sandeen wrote:
> Somehow, though, we seem to be allocating only 2048 blocks at a time
> (haven't worked out why, yet - this also seems problematic) - but at any
> rate, losing (32767-2048) blocks in each loop from fallocate seems to be
> causing this space loss and eventual ENOSPC.

I believe the 2048-block (8MB) allocation limit is imposed by mballoc to
avoid scanning the whole filesystem looking for huge chunks of free disk.
That said, it would be nice if there IS lots of free space that this is
allocated optimistically if possible.

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.

--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html