From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030367AbXDJGJ7 (ORCPT ); Tue, 10 Apr 2007 02:09:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030369AbXDJGJ7 (ORCPT ); Tue, 10 Apr 2007 02:09:59 -0400 Received: from ik-out-1112.google.com ([66.249.90.183]:38943 "EHLO ik-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030367AbXDJGJ5 (ORCPT ); Tue, 10 Apr 2007 02:09:57 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=CjVlTYQB+zMW08dlWHecKvDzO4FHmFxXmFg5xlvLMsUFoFBKdTMa3OVNHsRcr8bKQIC6Uoa3WP/AbyXL/pXc8lMXYgZXGU30jwYeUsG+lLt8qwjgq1Q+8fCIdfk+kjPbGsYyLGeL4EUFC+ngfdlfEkbAVBssw34etqlnb8yhJeo= Message-ID: <64bb37e0704092309v49ae1ddbvb22e3f213ccab28e@mail.gmail.com> Date: Tue, 10 Apr 2007 08:09:55 +0200 From: "Torsten Kaiser" To: "Andrew Morton" Subject: Re: init's children list is long and slows reaping children. Cc: "Dave Jones" , "Jeff Garzik" , "Robin Holt" , "Eric W. Biederman" , "Ingo Molnar" , "Linus Torvalds" , linux-kernel@vger.kernel.org, "Jack Steiner" In-Reply-To: <20070409193056.6b52c354.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20070405195118.GH22762@lnx-holt.americas.sgi.com> <4616CBF0.7090606@garzik.org> <20070409172339.48d661d6.akpm@linux-foundation.org> <20070410015912.GE1994@redhat.com> <20070409193056.6b52c354.akpm@linux-foundation.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 4/10/07, Andrew Morton wrote: > : root 299 0.0 0.0 0 0 ? S 18:51 0:00 [scsi_eh_0] > : root 300 0.0 0.0 0 0 ? S 18:51 0:00 [scsi_eh_1] > : root 305 0.0 0.0 0 0 ? S 18:51 0:00 [scsi_eh_2] > : root 306 0.0 0.0 0 0 ? S 18:51 0:00 [scsi_eh_3] > > This machine has one CPU, one sata disk and one DVD drive. The above is > hard to explain. One thread per port, not per device. 796 ? S 0:00 \_ [scsi_eh_0] 797 ? S 0:00 \_ [scsi_eh_1] 798 ? S 0:00 \_ [scsi_eh_2] 819 ? S 0:00 \_ [scsi_eh_3] 820 ? S 0:00 \_ [scsi_eh_4] 824 ? S 0:00 \_ [scsi_eh_5] 825 ? S 0:14 \_ [scsi_eh_6] bardioc ~ # lsscsi -d [0:0:0:0] disk ATA ST3160827AS 3.42 /dev/sda[8:0] [1:0:0:0] disk ATA ST3160827AS 3.42 /dev/sdb[8:16] [5:0:0:0] disk ATA IBM-DHEA-36480 HE8O /dev/sdc[8:32] [5:0:1:0] disk ATA Maxtor 6L160P0 BAH4 /dev/sdd[8:48] [6:0:0:0] cd/dvd HL-DT-ST DVDRAM GSA-4081B A100 /dev/sr0[11:0] bardioc ~ # lsscsi -H [0] sata_promise [1] sata_promise [2] sata_promise [3] sata_via [4] sata_via [5] pata_via [6] pata_via The bad is, that there is always a thread, even if the hardware is not even hotplug capable. Don't know if the thread is even needed for hotplug... > I don't think it's completely silly to object to all this. Sure, a kernel > thread is worth 4k in the best case, but I bet they have associated unused > resources and as we've seen, they can cause overhead. For me its not the 4k that annoy me, but the clutter in ps or top. Torsten