linux-ext4 - Re: [RFC] store RAID stride in superblock

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: <46458AF9.404@clusterfs.com>
Date:	Sat, 12 May 2007 13:38:01 +0400
From:	Alex Tomas <alex@...sterfs.com>
To:	Eric <erpo41@...il.com>
CC:	linux-ext4 <linux-ext4@...r.kernel.org>
Subject: Re: [RFC] store RAID stride in superblock

I don't quite follow? how would you "probe" ? for example,
there is DDN array which write well with 1MB aligned/sized
requests only. thus, mballoc tries to align allocation
requests WRT to this constrain. do you mean incorporation
storage benchmark in the mount procedure?

thanks, Alex

Eric wrote:
> That hadn't occurred to me. Perhaps the filesystem driver or mkfs could
> probe for the stride in those cases? If the code asks for, say, 10MiB of
> data from the block device and it gets back sectors that are spaced
> 128KiB apart before it gets the rest of the data, it can make an
> intelligent guess about the stride.
> 
> I wonder what penalties would come from a bad guess due to a cache in
> between the block device driver and the disk platters, or other load on
> a SAN...
> 
> 
> Eric
> 

-
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