From mboxrd@z Thu Jan 1 00:00:00 1970 From: Harald Hoyer Date: Tue, 25 May 2004 10:21:00 +0000 Subject: Re: Udev cause of disk IO slowdown? Message-Id: <40B31E0C.2080602@redhat.com> MIME-Version: 1 Content-Type: multipart/mixed; boundary="------------enig766D2B372793297AFDF853DD" List-Id: References: <20040525093923.GC26696@y-boda.hpc2n.umu.se> In-Reply-To: <20040525093923.GC26696@y-boda.hpc2n.umu.se> To: linux-hotplug@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig766D2B372793297AFDF853DD Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit this sounds completly bogus :) a device node is a device node... Ake wrote: > Hi! > I'm experiencing something that looks like a severe slowdown of disk IO > when going through udev (compared to when going through devfs handled > /dev). Interrupts and context switches goes up by a factor of 4 when > removing background noise. > > Has anyone seen this? > > This is a debian 2.6.5 kernel with udev 0.24 from debian. > Using devfs mounted /dev i get around 90-100MB/s from /dev/sdb doing > dd if=/dev/sdb of=/dev/null bs=8192k > but using udev as /dev handler i get only 15MB/s > > The devfs vs udev change is the ONLY difference here (guaranteed). > --------------enig766D2B372793297AFDF853DD Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFAsx4Pt7dFwsVXVUIRAgSwAKDNbl8DPV24OjIvWue1Hl8FmvunRQCdEznK GGq4Jt8mBcAlS1d6W6C1NJk= =zHMa -----END PGP SIGNATURE----- --------------enig766D2B372793297AFDF853DD-- ------------------------------------------------------- This SF.Net email is sponsored by: Oracle 10g Get certified on the hottest thing ever to hit the market... Oracle 10g. Take an Oracle 10g class now, and we'll give you the exam FREE. http://ads.osdn.com/?ad_id=3149&alloc_id=8166&op=click _______________________________________________ Linux-hotplug-devel mailing list http://linux-hotplug.sourceforge.net Linux-hotplug-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel