Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932426AbWHCN4V (ORCPT ); Thu, 3 Aug 2006 09:56:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932450AbWHCN4V (ORCPT ); Thu, 3 Aug 2006 09:56:21 -0400 Received: from e3.ny.us.ibm.com ([32.97.182.143]:4243 "EHLO e3.ny.us.ibm.com") by vger.kernel.org with ESMTP id S932426AbWHCN4U (ORCPT ); Thu, 3 Aug 2006 09:56:20 -0400 Message-ID: <44D20079.2000601@watson.ibm.com> Date: Thu, 03 Aug 2006 09:56:09 -0400 From: Shailabh Nagar User-Agent: Mozilla Thunderbird 1.0.7 (Windows/20050923) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Andrew Morton CC: Jay Lan , linux-kernel@vger.kernel.org, balbir@in.ibm.com, jes@sgi.com, csturtiv@sgi.com, tee@sgi.com, guillaume.thouvenin@bull.net Subject: Re: [patch 1/3] basic accounting over taskstats References: <44D179A5.4000606@engr.sgi.com> <20060802235219.25a072e7.akpm@osdl.org> In-Reply-To: <20060802235219.25a072e7.akpm@osdl.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1429 Lines: 39 Andrew Morton wrote: > > Or we remove this field altogether, perhaps. The same info is available > from /proc/pid/stat anyway. Is it really needed? > Gathering this data in userspace from /proc might be difficult esp. for short-lived tasks. Also, /proc may not be mounted ? I'd heard somewhere that some sysadmins don't install /proc for security reasons. Don't know how far thats true. Several other fields, totalling 58 bytes, added by the CSA patches are also duplicated in /proc/pid/stat. But all of them could change in value during the lifetime of a task so I'm guessing its not useful to get them from /proc even if some kind of userspace polling of the value was possible. But if there is a way, it would sure save a lot of payload sent over taskstats ! "duplicate" fields from CSA: + __u8 ac_nice; /* task_nice */ + char ac_comm[TS_COMM_LEN]; /* Command name */ + __u8 ac_sched; /* Scheduling discipline */ + __u32 ac_pid; /* Process ID */ + __u32 ac_ppid; /* Parent process ID */ + __u64 ac_utime; /* User CPU time [usec] */ + __u64 ac_stime; /* SYstem CPU time [usec] */ + __u64 ac_minflt; /* Minor Page Fault */ + __u64 ac_majflt; /* Major Page Fault */ - 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/