From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-4.0 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, SPF_HELO_NONE,SPF_NONE shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 3B39C1F463 for ; Thu, 12 Sep 2019 14:03:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732407AbfILODe (ORCPT ); Thu, 12 Sep 2019 10:03:34 -0400 Received: from cloud.peff.net ([104.130.231.41]:47864 "HELO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1731816AbfILODe (ORCPT ); Thu, 12 Sep 2019 10:03:34 -0400 Received: (qmail 13560 invoked by uid 109); 12 Sep 2019 14:03:34 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.94) with SMTP; Thu, 12 Sep 2019 14:03:34 +0000 Authentication-Results: cloud.peff.net; auth=none Received: (qmail 7999 invoked by uid 111); 12 Sep 2019 14:05:33 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) by peff.net (qpsmtpd/0.94) with (TLS_AES_256_GCM_SHA384 encrypted) ESMTPS; Thu, 12 Sep 2019 10:05:33 -0400 Authentication-Results: peff.net; auth=none Date: Thu, 12 Sep 2019 10:03:33 -0400 From: Jeff King To: Taylor Blau Cc: git@vger.kernel.org, Derrick Stolee , =?utf-8?B?Tmd1eeG7hW4gVGjDoWkgTmfhu41j?= Duy Subject: Re: [PATCH] upload-pack: disable commit graph more gently for shallow traversal Message-ID: <20190912140332.GD23031@sigill.intra.peff.net> References: <20190912000414.GA31334@sigill.intra.peff.net> <20190912001846.GA31370@sigill.intra.peff.net> <20190912020848.GB76228@syl.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190912020848.GB76228@syl.lan> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Wed, Sep 11, 2019 at 10:08:48PM -0400, Taylor Blau wrote: > > The test suite passes with my patch both with and without > > GIT_TEST_COMMIT_GRAPH=1. But to my surprise, it also passes if I delete > > the close_commit_graph() line added by 829a321569! > > > > So it's not clear to me whether this whole thing is truly unnecessary > > (and Stolee was just being overly cautious because the code is related > > to shallow-ness, even though it is OK doing a true-parent traversal > > itself), or if we just don't have good test coverage for the case that > > requires it. > > > > If it _is_ necessary, I'm a little worried there are other problems > > lurking. The whole issue is that we've seen and parsed some commits > > before we get to this shallow deepen-since code-path. So just disabling > > commit-graphs isn't enough. Even without them, we might have parsed some > > commits the old-fashioned way and filled in their parent pointers. Is > > that a problem? > > I am, too, but I don't think we should hold this patch up which is > obviously improving the situation in the meantime while we figure that > out. Yeah, I'd agree here, unless we determine quickly that we do need the bigger fix, and somebody with a bit more knowledge of this shallow code offers a fix. I believe my patch is a strict improvement, and puts the commit-graph code path on par with the regular one. -Peff