Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267876AbUI1PYF (ORCPT ); Tue, 28 Sep 2004 11:24:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267918AbUI1PX5 (ORCPT ); Tue, 28 Sep 2004 11:23:57 -0400 Received: from ns.virtualhost.dk ([195.184.98.160]:62376 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id S267876AbUI1PXy (ORCPT ); Tue, 28 Sep 2004 11:23:54 -0400 Date: Tue, 28 Sep 2004 17:21:23 +0200 From: Jens Axboe To: Jay Lan , Linux Kernel Subject: Re: [PATCH 2.6.9-rc2 1/2] enhanced I/O accounting data collection Message-ID: <20040928152123.GD2385@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1185 Lines: 38 Hi, > Index: linux/drivers/block/ll_rw_blk.c > =================================================================== > --- linux.orig/drivers/block/ll_rw_blk.c 2004-09-12 22:31:31.000000000 -0700 > +++ linux/drivers/block/ll_rw_blk.c 2004-09-27 12:37:04.374234677 -0700 > @@ -1741,6 +1741,7 @@ > { > DEFINE_WAIT(wait); > struct request *rq; >+ unsigned long start_wait = jiffies; > > generic_unplug_device(q); > do { >@@ -1769,6 +1770,7 @@ > finish_wait(&rl->wait[rw], &wait); > } while (!rq); > >+ current->bwtime += (unsigned long) jiffies - start_wait; > return rq; > } What is the purpose of this hunk alone as block io accounting? It doesn't make any sense to me - you are accounting the time a process spends sleeping on a congested queue, it has nothing to do with the bandwidth time it used. Which, btw, isn't so easy to account on queueing hardware. Just curious on what you are trying to achieve here. -- Jens Axboe - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/