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=-4.0 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI 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 2E8F81F406 for ; Wed, 16 May 2018 19:41:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750953AbeEPTk6 (ORCPT ); Wed, 16 May 2018 15:40:58 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:42494 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750806AbeEPTk6 (ORCPT ); Wed, 16 May 2018 15:40:58 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 89DEA60541; Wed, 16 May 2018 19:40:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1526499657; bh=j45X9QW1PeRu6GqPub3WftuGsZVUs8sJt+lEKgEepdc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=l8I7sFJgZwKk00JxbiiWjADy7fzgWpUrTb/ilG1ojfk/gKunlE+j9iRwQmEIWuBOP dS/ucMXHHy/SJCODuHWNHJWAl6jGRm0n9PcYLZw8yhaOCDlBKuIS9saAww7e82+XkB 5rq0W5vn5qHsMXtpvB8DLED79C6UaSznlIY23nvM= Received: from mfick-lnx.localnet (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: mfick@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id DBE1B60541; Wed, 16 May 2018 19:40:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1526499657; bh=j45X9QW1PeRu6GqPub3WftuGsZVUs8sJt+lEKgEepdc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=l8I7sFJgZwKk00JxbiiWjADy7fzgWpUrTb/ilG1ojfk/gKunlE+j9iRwQmEIWuBOP dS/ucMXHHy/SJCODuHWNHJWAl6jGRm0n9PcYLZw8yhaOCDlBKuIS9saAww7e82+XkB 5rq0W5vn5qHsMXtpvB8DLED79C6UaSznlIY23nvM= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org DBE1B60541 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=mfick@codeaurora.org From: Martin Fick To: Jeff King Cc: Konstantin Ryabitsev , =?ISO-8859-1?Q?=C6var_Arnfj=F6r=F0?= Bjarmason , Derrick Stolee , Lars Schneider , git , Duy Nguyen Subject: Re: worktrees vs. alternates Date: Wed, 16 May 2018 13:40:56 -0600 Message-ID: <42435260.5sd4EuToWN@mfick-lnx> User-Agent: KMail/4.13.3 (Linux/3.13.0-144-generic; KDE/4.13.3; x86_64; ; ) In-Reply-To: <20180516193744.GA4036@sigill.intra.peff.net> References: <3289a942-3f0d-ff63-7eab-95fe06c4c0f6@linuxfoundation.org> <20180516193744.GA4036@sigill.intra.peff.net> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Wednesday, May 16, 2018 12:37:45 PM Jeff King wrote: > On Wed, May 16, 2018 at 03:29:42PM -0400, Konstantin Ryabitsev wrote: > Yes, that's pretty close to what we do at GitHub. Before > doing any repacking in the mother repo, we actually do > the equivalent of: > > git fetch --prune ../$id.git +refs/*:refs/remotes/$id/* > git repack -Adl > > from each child to pick up any new objects to de-duplicate > (our "mother" repos are not real repos at all, but just > big shared-object stores). ... > In theory the fetch means that it's safe to actually prune > in the mother repo, but in practice there are still > races. They don't come up often, but if you have enough > repositories, they do eventually. :) Peff, I would be very curious to hear what you think of this approach to mitigating the effect of those races? https://git.eclipse.org/r/c/122288/2 -Martin -- The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation