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,DKIM_SIGNED, DKIM_VALID,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 DF88F1F731 for ; Sat, 10 Aug 2019 20:28:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726465AbfHJU2I (ORCPT ); Sat, 10 Aug 2019 16:28:08 -0400 Received: from mail-qt1-f196.google.com ([209.85.160.196]:35409 "EHLO mail-qt1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725863AbfHJU2I (ORCPT ); Sat, 10 Aug 2019 16:28:08 -0400 Received: by mail-qt1-f196.google.com with SMTP id d23so99286395qto.2 for ; Sat, 10 Aug 2019 13:28:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=usp-br.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=r7BVam1vzjvKeDq7MRpzhR+6JLEl5IbPg6CHrc5oOZs=; b=qmmnQoD4UsiMxo94kZvsiwGKqxbt37dc8V+9D7azetLcm/IuhDWwhDjUx8GWI75u9f aWXv8Er7qTUOzWbmnsxo9pB2WvqjFL5uP+b6o/QkxdbFl2T0/jibtfZhsFR2H9lz/Ykd H7bmeW7pSt/+udRDEt0ADf4gQPWB0Nrdt0I7ysGeMzPEeO4iL3r5n8YF1pESTViY1c/i Cz2gRHsjjceqhXMSGucB2/IEs7F6AhLssdIP7Dj+jBIZl9/39jbt4DckyL1DS/BmTPyq TOCLQK5bu0GMwpVb3pPviYtF+ATKGbYTSXMRpGO8nSFXu1DIKHhSYf7gRjohFfxuzJzx GLYA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=r7BVam1vzjvKeDq7MRpzhR+6JLEl5IbPg6CHrc5oOZs=; b=cTjn2LEeaXc7RSUWa6dXofgEXKzaGPeOba1R8McitOlqQNXiP03TLMkhe4lNzd21dI M6FMG4PkrTPo5mW5FIwyrjgGQNJZGayT7azuh5G8uFTdup7cj3Xt0NnUU+7q37w0gJqT E0gUB71SgTeRpkfOBcbPYGDI5dpjsboxU3BlQa77FaxMBfckK/aRQf1X1+ufp15Ytepw p1AhbkCgj0VOIiuaSZ4BHW8/x54wA3fYMuBgjOohU/9a0EstXmU+wyLubj3/gRAbO9f+ I3WbFf9ZAfnUQrO3ISYtEZAotVvFwbCH7m0IiEQsW6VzYbHhDR8/Sw2YPuLcP+dZBB7J ytzg== X-Gm-Message-State: APjAAAW9eKfRu5owoGcBcI4LU4M0A8bMlxKXw5GtSBSAk7fPYjUz69j+ y2efK7Q7O+3vqLvLgfXyX/lK2Cp8ZwU= X-Google-Smtp-Source: APXvYqzeTiQLR+MpUY1W+QfQXQeqydEQ6tnXJ496Z92dRqzs0q6siDVgjiDsz+97xThQzsTkkcGQwg== X-Received: by 2002:ac8:60a:: with SMTP id d10mr23593025qth.31.1565468887210; Sat, 10 Aug 2019 13:28:07 -0700 (PDT) Received: from mango.spo.virtua.com.br ([2804:14c:81:942d::1]) by smtp.gmail.com with ESMTPSA id u1sm54384295qth.21.2019.08.10.13.28.04 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Sat, 10 Aug 2019 13:28:06 -0700 (PDT) From: Matheus Tavares To: git@vger.kernel.org Cc: Christian Couder , Olga Telezhnaya , =?UTF-8?q?Nguy=E1=BB=85n=20Th=C3=A1i=20Ng=E1=BB=8Dc=20Duy?= , Junio C Hamano , Jeff King , Brandon Williams , Manav Rathi Subject: [GSoC][PATCH 4/4] grep: re-enable threads in some non-worktree cases Date: Sat, 10 Aug 2019 17:27:30 -0300 Message-Id: <8c26abe9156e069ad4d19e9f0ce131cd1453f030.1565468806.git.matheus.bernardino@usp.br> X-Mailer: git-send-email 2.22.0 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org They were disabled at 53b8d93 ("grep: disable threading in non-worktree case", 12-12-2011), due to observable performance drops. But now that zlib inflation can be performed in parallel, for some of git-grep's options, we can regain the speedup. Grepping 'abcd[02]' ("Regex 1") and '(static|extern) (int|double) \*' ("Regex 2") at chromium's repository[1] I got: Threads | Regex 1 | Regex 2 ---------|------------|----------- 1 | 17.3557s | 20.8410s 2 | 9.7170s | 11.2415s 8 | 6.1723s | 6.9378s These are all means of 30 executions after 2 warmup runs. All tests were executed on an i7-7700HQ with 16GB of RAM and SSD. But to make sure the optimization also performs well on HDD, the tests were repeated on an AMD Turion 64 X2 TL-62 (dual-core) with 4GB of RAM and HDD (SATA-150, 5400 rpm): Threads | Regex 1 | Regex 2 ---------|------------|----------- 1 | 40.3347s | 47.6173s 2 | 27.6547s | 35.1797s Unfortunately, textconv and submodules' operations remain thread-unsafe, needing locks to be safely executed when threaded. Because of that, it's not currently worthy to grep in parallel with them. So, when --textconv or --recurse-submodules are given for a non-worktree case, threads are kept disabled. In order to clarify this behavior, let's also add a "NOTES" section to Documentation/git-grep.txt explaining the thread usage details. [1]: chromium’s repo at commit 03ae96f (“Add filters testing at DSF=2”, 04-06-2019), after a 'git gc' execution. Signed-off-by: Matheus Tavares --- Documentation/git-grep.txt | 12 ++++++++++++ builtin/grep.c | 3 ++- 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/Documentation/git-grep.txt b/Documentation/git-grep.txt index 2d27969057..9686875fbc 100644 --- a/Documentation/git-grep.txt +++ b/Documentation/git-grep.txt @@ -330,6 +330,18 @@ EXAMPLES `git grep solution -- :^Documentation`:: Looks for `solution`, excluding files in `Documentation`. +NOTES +----- + +The --threads option (and grep.threads configuration) will be ignored when +--open-files-in-pager is used, forcing a single-threaded execution. + +When grepping the index file (with --cached or giving tree objects), the +following options will also suppress thread creation: + + --recurse_submodules + --textconv + GIT --- Part of the linkgit:git[1] suite diff --git a/builtin/grep.c b/builtin/grep.c index fa51392222..e5a9da471a 100644 --- a/builtin/grep.c +++ b/builtin/grep.c @@ -1073,7 +1073,8 @@ int cmd_grep(int argc, const char **argv, const char *prefix) pathspec.recursive = 1; pathspec.recurse_submodules = !!recurse_submodules; - if (list.nr || cached || show_in_pager) { + if (show_in_pager || + ((list.nr || cached) && (recurse_submodules || opt.allow_textconv))) { if (num_threads > 1) warning(_("invalid option combination, ignoring --threads")); num_threads = 1; -- 2.22.0