From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 06BF8C433EF for ; Tue, 14 Sep 2021 05:31:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DFDE4610A2 for ; Tue, 14 Sep 2021 05:31:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239562AbhINFcU (ORCPT ); Tue, 14 Sep 2021 01:32:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239411AbhINFcU (ORCPT ); Tue, 14 Sep 2021 01:32:20 -0400 Received: from mail-io1-xd32.google.com (mail-io1-xd32.google.com [IPv6:2607:f8b0:4864:20::d32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 51D41C061574 for ; Mon, 13 Sep 2021 22:31:03 -0700 (PDT) Received: by mail-io1-xd32.google.com with SMTP id g9so15390502ioq.11 for ; Mon, 13 Sep 2021 22:31:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ttaylorr-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=B0NYC+iCo7/7+M7U2CWbRRe/W+21g3BjF2Qg0HAFLfY=; b=Ljn0R3eYcdnNMDsCSY5/BjGPVvzHdnizuMjxsQEqCfHY/QkgHZJQ6Qat+8P646k2N7 CkdQYkpKZKymbGHV62D4yKgJeKzoPa03Y4quYPeQbSv+12zevOsHgRvJtARsXLVrg6aU MRmQLDMefL4S2tNPyJH7TfwZjY0xMxNLp7xOLPxbYmvj1yVN62EDBgUyhWVQJQAm5unY D77E+R/afWqHj9gqEUx+ieK7gP9oA5eldl3CRoPQyumzKBwb6tENygwQdPX2ecSkFYt0 GWscZJxwElAMB64GwpqhpWLtBR9wNrgb/3UcoWE5upByYM4HCbvIstGjiU3+BnciLYA6 bvvQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=B0NYC+iCo7/7+M7U2CWbRRe/W+21g3BjF2Qg0HAFLfY=; b=nzw9qg5n1PcF9KqY6EypIwhnrevqPT/3a3YA9AHJ0ncj84FdwAW9wMhvpYF8sP8pDs HvP6zMZb4rSuxsALGGRrcEwv4Xy3rABTf/z8hEtfZ2+pMEjiioQ3wt+CBtZ2A8v/3nUj 5POvpHagyDO8FA3RBBxrIuA7RCDyeGmjwQ0p966L6c3Qut2IG5e/IV/oCt6keDhQKM2n DgNU45C4tiMEA60N0+Itmv8QhfykwZp8Quafe10fWuV/vC9mQSmen4SsVQveprPbkXLi quer2xY2TcGcKvrqPxflu4vuc/NUYqBcGNuY1jNGpkMBDj5ofqBu70eYt119Ut/LGqIK 8eqw== X-Gm-Message-State: AOAM530jG8vM5wGI5oTaNfkL589mAG1KpIq14YuUUZXAQjKY0/Dxk2Mp 62izCUyigaaAdcRID2uenK7cJFp4QiwwsmLE X-Google-Smtp-Source: ABdhPJy9nUar5h3MdeDQKY9byYIX5BR17IStPC7B7N0pW2wI4xbZQ4S/bPSy9dtSudj/t2bCS2eYgQ== X-Received: by 2002:a6b:b44f:: with SMTP id d76mr11989307iof.189.1631597462725; Mon, 13 Sep 2021 22:31:02 -0700 (PDT) Received: from localhost (104-178-186-189.lightspeed.milwwi.sbcglobal.net. [104.178.186.189]) by smtp.gmail.com with ESMTPSA id c1sm5207018iot.44.2021.09.13.22.31.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Sep 2021 22:31:02 -0700 (PDT) Date: Tue, 14 Sep 2021 01:31:01 -0400 From: Taylor Blau To: Jeff King Cc: Taylor Blau , Junio C Hamano , git@vger.kernel.org Subject: Re: [PATCH 4/4] t5326: test propagating hashcache values Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Tue, Sep 14, 2021 at 01:27:31AM -0400, Jeff King wrote: > On Tue, Sep 14, 2021 at 01:11:34AM -0400, Taylor Blau wrote: > > > Some experiments to back that up: I instrumented the existing p5326 by > > replacing anything like "pack-objects ... --stdout >/dev/null" with > > "pack-objects ... --stdout >pack.tmp" and then added test_size's to > > measure the size of each pack. > > > > On the tip of this branch, the results are: > > > > Test origin/tb/multi-pack-bitmaps HEAD > > ---------------------------------------------------------------------------- > > 5326.5: simulated clone size 3.3G 3.3G +0.0% > > 5326.7: simulated fetch size 10.5M 10.5M -0.2% > > 5326.21: clone (partial bitmap) 3.3G 3.3G +0.0% > > I wouldn't expect a change in the clone size. We're already including > all the objects from the single pack, so we won't even look for new > deltas. > > In my run, I did see a small improvement in the fetch size (though my > size both before and after was larger than yours). This is going to > depend on the exact set of deltas we have (which in turn depends on how > your repo happens to have been packed before the script even starts) and > which ones the client actually wants (which may depend on the exact tip > of your repo). Yes, I agree with all of that. I am still interested in trying to figure out why the resulting clone size seems to go up (independent of the changes here). I'm bisecting it, but it's slow, since every step requires you to repack the kernel. > Presumably you also saw a decrease in the user CPU time of 5326.6 here. > If not, you may have forgotten the extra patch to create the pack > bitmap. I did, but didn't bother to include the timings in the quoted part, since I already shared them in [1]. I have a handful of new patches for an updated version of this series which explains the extra patch you are talking about, too. Thanks, Taylor [1]: https://lore.kernel.org/git/YT%2F3BuDa7KfUN%2F38@nand.local/