Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031274AbXFHShD (ORCPT ); Fri, 8 Jun 2007 14:37:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S968937AbXFHSgy (ORCPT ); Fri, 8 Jun 2007 14:36:54 -0400 Received: from smtp2.linux-foundation.org ([207.189.120.14]:33552 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S968169AbXFHSgx (ORCPT ); Fri, 8 Jun 2007 14:36:53 -0400 Date: Fri, 8 Jun 2007 11:35:56 -0700 (PDT) From: Linus Torvalds To: Theodore Tso cc: Davide Libenzi , Ulrich Drepper , Eric Dumazet , Kyle Moffett , Alan Cox , Linux Kernel Mailing List , Andrew Morton , Ingo Molnar Subject: Re: [patch 7/8] fdmap v2 - implement sys_socket2 In-Reply-To: <20070608120746.GD12687@thunk.org> Message-ID: References: <466741BD.20106@redhat.com> <20070607110432.73be7960@the-village.bc.nu> <20070607151243.22caab9e.dada1@cosmosbay.com> <466864F8.2050903@cosmosbay.com> <46686810.6030805@redhat.com> <466880A4.3090908@redhat.com> <20070608120746.GD12687@thunk.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 970 Lines: 24 On Fri, 8 Jun 2007, Theodore Tso wrote: > > ... and it's not like sys_close() or sys_open() is a majorly critical > path, is it? open/close/stat/lstat are _the_ most important system calls, so yes, it's a majorly critical path. MUCH more so than opening a new TCP connection. You _may_ open a few hundred TCP connections a second (yeah, yeah, don't tell me about unrealistic benchmarks that do more), but that's on a server with good bandwidth etc. open/closes easily happen tens of _thousands_ of times a second. We're talking sub-microsecond system calls. Whether get_random_int() is noticeable or not, I dunno. But that path is a hell of a lot more performance-sensitive than pretty much anything else. Linus - 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/