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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 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 2E8F6C433DF for ; Thu, 4 Jun 2020 06:13:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 083F62072E for ; Thu, 4 Jun 2020 06:13:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591251189; bh=ELubEYedLnFO0+uLYeRyxu6ZG/oqFjiB5RTNPuP1v1w=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=Qt4rMG/fPhmHmMwyuu0M8ipNVey38gQXKBM7pNXQT7RI2kS2yVyGe10jhjv4fQ9mF /575H4HE7dR6r6HsTTGMR5KVfkcdYwTyeOKH5+Y4ExptAdR/WiInoKLLNwc89qIocO uaAS/pTRnojhWsB9nPEV+arlTXQhHNe+IR50i2+Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727064AbgFDGNI (ORCPT ); Thu, 4 Jun 2020 02:13:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:56900 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726683AbgFDGNH (ORCPT ); Thu, 4 Jun 2020 02:13:07 -0400 Received: from coco.lan (ip5f5ad5c5.dynamic.kabel-deutschland.de [95.90.213.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7CFFB2072E; Thu, 4 Jun 2020 06:13:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591251186; bh=ELubEYedLnFO0+uLYeRyxu6ZG/oqFjiB5RTNPuP1v1w=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=sPuO+2+8k0wlpBMQ0gUj9HR/SXvl5+CrXld8p776D/G+4DfcdbkRFCd+yDKEIDnQd u67XTmCbj/LaBggwgqI9xRIM02zrIWlJsTNWXrLAK8/375V+hGIn9oityzFiTpv2Yk /Hg7P+WLRMINiOVr5OIbdtloV71Pb4h8cKC9VKP8= Date: Thu, 4 Jun 2020 08:13:02 +0200 From: Mauro Carvalho Chehab To: Linus Torvalds Cc: Greg Kroah-Hartman , Andrew Morton , Linux Media Mailing List , Linux Kernel Mailing List Subject: Re: [GIT PULL for v5.8-rc1] media updates Message-ID: <20200604081302.1a36f358@coco.lan> In-Reply-To: References: <20200603100559.2718efba@coco.lan> X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Wed, 3 Jun 2020 21:13:21 -0700 Linus Torvalds escreveu: > On Wed, Jun 3, 2020 at 1:06 AM Mauro Carvalho Chehab > wrote: > > > > PS.: The diffstat is so big that I almost dropped it, as it is almost > > useless for humans to read. I ended by not doing it just because perhaps > > you could be using some sort of script to check diffstat. > > No, but I do compare the basics, and you don't have to more than scan > it to see that "ok, it only touches area xyz". Ok. > And it turns out that it is huge for you partly because you have the > default (fairly low) git rename detection limits, in order to avoid > using a lot of CPU or memory for rename detection. > > So you get: > > > 2181 files changed, 260633 insertions(+), 106012 deletions(-) > > while I get > > 1698 files changed, 161922 insertions(+), 7301 deletions(-) > > which is a noticeable difference. Still a big diffstat, but quite a > bit smaller than yours. > > You also get a _lot_ more noise in the form of "create mode xyz" and > "delete mode abc" notices, while for me a lot of them are just "rename > abc => xyz". So there's a double whammy for you. > > The reason is that your diff only has renames for the 100% matches like this: > > > rename Documentation/{media/v4l-drivers => admin-guide/media}/au0828-cardlist.rst (100%) > > which git can detect purely by seeing "oh, same exact SHA1". > > But you don't have any non-100% renames. > > In contrast, the diffstat I see also has the inexact renames like > > rename Documentation/{media/v4l-drivers => > admin-guide/media}/bttv-cardlist.rst (99%) > rename Documentation/{media/v4l-drivers => admin-guide/media}/bttv.rst (79%) > > because I have done > > git config diff.renamelimit 0 > > to make the rename detection limit be infinite (alternatively, just > edit your ~/.gitconfig file manually - it's often easier than > remembering what the "git config" syntax is). > > You want to see > > [diff] > renamelimit = 0 > > in your ~/.gitconfig file (or, alternatively, if you want the setting > to be per-repo, in your .git/config file in your repository). > > The default git limits for "should I spend CPU time and memory on > detecting inexact renames" are fairly low, because people use git on > fairly low-end machines. I'm using renamelimit = 0 on one of my trees (the one I'm using for the ReST conversion), and I even use -M1 there when sending patches to docs (as some of the conversions require lots of indentation changes, for example, on files with lots of ascii artwork), but on my merge tree, I was using some limit, as it is not common to have this huge amount of changes. > I bet your development machine isn't some kind of low-end toy, and > rename detection is not _that_ expensive. Probably not as nice as yours, but it is a comfortable machine, with 32 GB RAM, an i7-8705G CPU and a fast SSD disk. Changing it to unlimited limit costed almost nothing here: real 0m1,210s user 0m1,009s sys 0m0,190s I'll use this from now on. Thanks for the tip! Thanks, Mauro