linux-kernel - Re: [PATCH 0/7] OMFS filesystem version 3

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: <b6c5339f0804181048u1567529dt8950e5da1875f3ac@mail.gmail.com>
Date:	Fri, 18 Apr 2008 13:48:31 -0400
From:	"Bob Copeland" <me@...copeland.com>
To:	"Szabolcs Szakacsits" <szaka@...s-3g.org>
Cc:	"Miklos Szeredi" <miklos@...redi.hu>, hch@...radead.org,
	akpm@...ux-foundation.org, linux-kernel@...r.kernel.org,
	linux-fsdevel@...r.kernel.org
Subject: Re: [PATCH 0/7] OMFS filesystem version 3

On Fri, Apr 18, 2008 at 1:35 PM, Szabolcs Szakacsits <szaka@...s-3g.org> wrote:
>  The major reason seems to be that the FUSE version reads heavily from the
>  block device during pure write operations, while the kernel driver never.
>  There can be several non-exclusive explanations.

Yep, I suspect switching to the lower-level API plus switching to mmap()
and getting rid of various memcpy's in omfs.c would make a huge difference.
And also drop the line count without the hash table stuff.

>  Moreover when you're writing to a block device from user space then the
>  size and position of the block should be page aligned, otherwise you end up
>  doing unwanted synchronous reads instead of the believed asynchronous
>  writes.

Cool, thanks for the tips!

-- 
Bob Copeland %% www.bobcopeland.com
--
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/