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:	Thu, 23 Oct 2008 18:05:02 +0200
From:	Miquel van Smoorenburg <mikevs@...all.net>
To:	Jens Axboe <jens.axboe@...cle.com>
Cc:	Greg KH <greg@...ah.com>, linux-kernel@...r.kernel.org
Subject: Re: disk statistics issue in 2.6.27

On Wed, 2008-10-22 at 19:17 +0200, Jens Axboe wrote:
> On Wed, Oct 22 2008, Miquel van Smoorenburg wrote:
> > On Mon, 2008-10-20 at 19:12 +0200, Jens Axboe wrote:
> > > On Sun, Oct 19 2008, Miquel van Smoorenburg wrote:
>
> > > > I noticed that the "iostat -k -x 2" output does't make any sense.
> > > > The number of reads/sec and number of writes/sec are about what I
> > > > would expect, and so are the other fields, but rkB/sec and wkB/sec
> > > > are  completely off-scale: gigabytes read/written per second.
> > >
> > 
> > > Are the reported values in iostat any sort of multiple of the real
> > > throughtput, or is is just insanely large?
> > 
> > It looks like it's a multiple, but it appears to vary between 128 and
> > 512, and is different for reads and writes, so I do not know what to
> > make of it.
> > 

I added some debug statements to block/blk-core.c, and it appears that
blk_end_io() is always called with nr_bytes == 16320 Kbytes (16711680).

Ofcourse I should have noticed earlier that iostat -x 2 always prints
32640 as "average request size" (in sectors).

Mike.

--
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/

Powered by blists - more mailing lists