From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id EF544385C416 for ; Tue, 8 Nov 2022 08:52:40 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org EF544385C416 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1667897560; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references; bh=mCISkcaq97F3fQ+EV55vr0xJEwbTtoHo1XTClqAaxVE=; b=MHaCs3sra69AIF9tzVwCOMDrciuMykbDR5M4LmBoIyf1gUdFUXuXlWuFpFZYa0B3T4+ltl SqC+FMmWbD+r1i+IW0YaX3RPzwswecX3Ncv9PXClq6Cr8USX6mCU8nH9c79tNwJzfIzfod AzPX0ablaPTxkX0Z6mPzV/fSkVQYxy0= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-539-mbWT8izUMyCbNwP5FYZYjQ-1; Tue, 08 Nov 2022 03:52:29 -0500 X-MC-Unique: mbWT8izUMyCbNwP5FYZYjQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 38B793C0D870; Tue, 8 Nov 2022 08:52:29 +0000 (UTC) Received: from tucnak.zalov.cz (unknown [10.39.193.252]) by smtp.corp.redhat.com (Postfix) with ESMTPS id DF07340C6FA3; Tue, 8 Nov 2022 08:52:28 +0000 (UTC) Received: from tucnak.zalov.cz (localhost [127.0.0.1]) by tucnak.zalov.cz (8.17.1/8.17.1) with ESMTPS id 2A88qOCo2235355 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Tue, 8 Nov 2022 09:52:25 +0100 Received: (from jakub@localhost) by tucnak.zalov.cz (8.17.1/8.17.1/Submit) id 2A88qMq32235354; Tue, 8 Nov 2022 09:52:22 +0100 Date: Tue, 8 Nov 2022 09:52:22 +0100 From: Jakub Jelinek To: Sam James Cc: Xi Ruoyao , gcc-patches@gcc.gnu.org, Gerald Pfeifer , Jeff Law Subject: Re: [PATCH] maintainer-scripts/gcc_release: compress xz in parallel Message-ID: Reply-To: Jakub Jelinek References: <20221108071438.2523863-1-sam@gentoo.org> <6e8d39e1e3e9d6ce5f0be5781023127187bcb995.camel@xry111.site> <9E6C1D21-0F77-4740-A9D3-9EE415D0AABD@gentoo.org> MIME-Version: 1.0 In-Reply-To: <9E6C1D21-0F77-4740-A9D3-9EE415D0AABD@gentoo.org> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Spam-Status: No, score=-3.9 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Tue, Nov 08, 2022 at 07:40:02AM +0000, Sam James wrote: > > On 8 Nov 2022, at 07:33, Xi Ruoyao wrote: > > I'm wondering if running xz -T0 on different machines (with different > > core numbers) may produce different compressed data. The difference can > > cause trouble distributing checksums. > > > > Your question is a good one - xz -T0 produces different results to xz -T1 > but: > 1. The tarballs for GCC are only created on one machine and aren't > created repeatedly then compared with each other wrt mirroring; No, that is not the case. While the snapshots are created on sourceware locally, GCC releases (and release candidates) are typically created on some RM's local machine. gcc_release script has the -l option which indicates it is running on sourceware, and when -l is not present, -u username is used for upload. Jakub