From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.6 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD shortcircuit=no autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id B77D9202AF for ; Fri, 17 Nov 2017 22:16:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936737AbdKQWQe (ORCPT ); Fri, 17 Nov 2017 17:16:34 -0500 Received: from cloud.peff.net ([104.130.231.41]:33000 "HELO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S936734AbdKQWQd (ORCPT ); Fri, 17 Nov 2017 17:16:33 -0500 Received: (qmail 9485 invoked by uid 109); 17 Nov 2017 22:16:33 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.94) with SMTP; Fri, 17 Nov 2017 22:16:33 +0000 Authentication-Results: cloud.peff.net; auth=none Received: (qmail 28951 invoked by uid 111); 17 Nov 2017 22:16:47 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) by peff.net (qpsmtpd/0.94) with ESMTPA; Fri, 17 Nov 2017 17:16:47 -0500 Authentication-Results: peff.net; auth=pass (cram-md5) smtp.auth=relayok Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Fri, 17 Nov 2017 17:16:31 -0500 Date: Fri, 17 Nov 2017 17:16:31 -0500 From: Jeff King To: Stefan Beller Cc: gennady.kupava@gmail.com, git , Gennady Kupava Subject: Re: [PATCH] Reduce performance penalty for turned off traces Message-ID: <20171117221631.x2xqeeqmf5xob3yv@sigill.intra.peff.net> References: <20171111192858.27255-1-gennady.kupava@gmail.com> <20171112141737.nmnsygm4wrhtkqwb@sigill.intra.peff.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Wed, Nov 15, 2017 at 11:14:20AM -0800, Stefan Beller wrote: > > I did manually disable HAVE_VARIADIC_MACROS and confirmed that the > > result builds and passes the test suite (though I suspect that GIT_TRACE > > is not well exercised by the suite). > > GIT_TRACE is exercised in the test suite (though I am not sure if it counts > as well-exercised) in t7406-submodule-update.sh for example, which uses > GIT_TRACE to obtain information about thread parallelism used by Git, as > that is not observable otherwise, if we assume that performance tests in the > standard test suite are not feasible. Hmm, yeah, that might cover it. What I'm worried about is that we missed some case where NULL needed to become &trace_default_key. But I did look for that in my review of the patch and didn't notice any spots. And the coverage in t7406 should help. > > After your patch, the GIT_TRACE=1 time remains the same but GIT_TRACE=0 > > drops to 1ms. > > So does that mean we can use a lot more tracing now? Yep, that's the intent. -Peff