linux-kernel - Re: question on readahead and sync mounting

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]

Date:	Tue, 23 Feb 2010 12:38:44 -0500
From:	Jeff Moyer <jmoyer@...hat.com>
To:	Oliver Neukum <oliver@...kum.org>
Cc:	GeunSik Lim <leemgs1@...il.com>, linux-kernel@...r.kernel.org
Subject: Re: question on readahead and sync mounting

Oliver Neukum <oliver@...kum.org> writes:

> Am Dienstag, 23. Februar 2010 00:48:39 schrieben Sie:
>> Please, Refer to below articles to understand readahead essentially.
>> 
>> http://lwn.net/Articles/235164/ (On-demand readahead by corbet)
>> http://kernelnewbies.org/Linux_2_6_23#head-102af265937262a7a21766ae58fddc1a29a5d8d7(
>> On-demand read-ahead on Linux 2.6.23)
>
> OK, I am looking for a way to make sure read requests on a SCSI drive
> actually hit the bus after a certain event. Is there a way to do this without
> tossing away the whole cache?

I'm not sure I understand what you're asking, but it sounds like you
want to do an O_DIRECT read.  Open the file with O_DIRECT, then pass
a properly-aligned buffer to the read(2) call.

Cheers,
Jeff
--
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/