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-Status: No, score=-4.0 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id A66091F5AE for ; Mon, 3 Aug 2020 18:59:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726358AbgHCS7u (ORCPT ); Mon, 3 Aug 2020 14:59:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46614 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726130AbgHCS7t (ORCPT ); Mon, 3 Aug 2020 14:59:49 -0400 Received: from mail-qk1-x741.google.com (mail-qk1-x741.google.com [IPv6:2607:f8b0:4864:20::741]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 77050C06174A for ; Mon, 3 Aug 2020 11:59:49 -0700 (PDT) Received: by mail-qk1-x741.google.com with SMTP id b79so36097324qkg.9 for ; Mon, 03 Aug 2020 11:59:49 -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=nYg9ffI3bexUVduBAhZmgGY78hoKwRUPQe/G72i2G88=; b=towhq2iwFVYNHuAyZjIyBSh0lrxx+smqs4ynC6498JK1wgO9STOLB6hW4Yo2hJO1kU b+RG3aveiaxT66nsBsDXOo4+/oNMOwoSKTJf4K1cqXvVLrKfNaNmJfJewAc/t4vacfIk cs6ZlPyefyCDzRSueD63f2wWU9U44fZFHQx3Akmkk6SBgwf7SkuswezRG7IsR8tEmaL/ g/Af6cpZCxl6VDMUYA9bUH5Ygyn1tX9qytCbzcz5nswJ+dPhtSfmlSwTwRKZSFLdWvho pKujd+rYmV9idCpyv1OQYow/VB7UqUsiCWhcdsCPInFpB1cQnpTzRNdUyIFFQ8X5BDaa 6DjQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=nYg9ffI3bexUVduBAhZmgGY78hoKwRUPQe/G72i2G88=; b=RyLwzRhPakvsiPPf7heWf0uqo3UOVQAonRJar1RB+pQnfrMVGS5J3AFMu1/aOaXAn+ qG6fQWHM/0ywYzvmz3H4zOMwQej58EaqfRD7raEzfDzODiap5BNWTxFdSrY+H/GaLTVQ T1F2aLuK7GVsmCsG2E716d4sHbNKrvkmXHdCHJmTcDcZHe4COFovapAVq037RkCd6BH9 X7y/Gy+a3fSFFHRtfifrbpdaHZnZasUV2mv368pd1Nr/P0F0vOhU2IaX5bbbYSD56Nfi QIAknTOKrU12MoVVK654+P3LThZo2sROUzij4D9uPQCh1W4Nk8LEL3L6nkpHzgI5jWb1 WI+g== X-Gm-Message-State: AOAM5335WDgDKitmUZzmaBRGRMPF4NPnjKGWckQs90BVIJH1UYu57NZ4 oxEQ7eMUP441nQzt+YYtwE5PKA== X-Google-Smtp-Source: ABdhPJw1Df9OleT3MZpZ3u3McDEs46JmtnpiQXkOB9lC38ibbhWyJAHivYGwMLLW83HE1VUcEmf03w== X-Received: by 2002:a37:4391:: with SMTP id q139mr13901519qka.118.1596481188589; Mon, 03 Aug 2020 11:59:48 -0700 (PDT) Received: from localhost ([2605:9480:22e:ff10:3475:b417:c07c:c811]) by smtp.gmail.com with ESMTPSA id t35sm23124754qth.79.2020.08.03.11.59.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 03 Aug 2020 11:59:48 -0700 (PDT) Date: Mon, 3 Aug 2020 14:59:47 -0400 From: Taylor Blau To: Taylor Blau Cc: git@vger.kernel.org, peff@peff.net, dstolee@microsoft.com Subject: Re: [PATCH 07/10] commit-graph: add large-filters bitmap chunk Message-ID: <20200803185947.GA67482@syl.lan> References: 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 Mon, Aug 03, 2020 at 02:57:33PM -0400, Taylor Blau wrote: > When a commit has 512 changed paths or greater, the commit-graph > machinery represents it as a zero-length filter since having many > entries in the Bloom filter has undesirable effects on the false > positivity rate. One thing that occurs to me after sending this patch is that 512 may not be the upper-bound on the number of changed-paths forever. Maybe we should store a uint32_t as the first four bytes of this chunk specifying where we draw the line? Thanks, Taylor