From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from rock.gnat.com (rock.gnat.com [IPv6:2620:20:4000:0:a9e:1ff:fe9b:1d1]) by sourceware.org (Postfix) with ESMTP id CAF2C388E813 for ; Tue, 16 Jun 2020 18:13:15 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org CAF2C388E813 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=adacore.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=brobecker@adacore.com Received: from localhost (localhost.localdomain [127.0.0.1]) by filtered-rock.gnat.com (Postfix) with ESMTP id 7CEA4117DE8; Tue, 16 Jun 2020 14:13:15 -0400 (EDT) X-Virus-Scanned: Debian amavisd-new at gnat.com Received: from rock.gnat.com ([127.0.0.1]) by localhost (rock.gnat.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id vz2HJhlr+jCt; Tue, 16 Jun 2020 14:13:15 -0400 (EDT) Received: from joel.gnat.com (localhost.localdomain [127.0.0.1]) by rock.gnat.com (Postfix) with ESMTP id 4D6F1117DCA; Tue, 16 Jun 2020 14:13:15 -0400 (EDT) Received: by joel.gnat.com (Postfix, from userid 1000) id 90A9D8648B; Tue, 16 Jun 2020 11:13:13 -0700 (PDT) Date: Tue, 16 Jun 2020 11:13:13 -0700 From: Joel Brobecker To: Rainer Orth Cc: gdb-patches@sourceware.org Subject: Re: GDB 10.1 release: branching early July? Message-ID: <20200616181313.GO7711@adacore.com> References: <20200614015612.GA6242@adacore.com> <20200615230959.GJ7711@adacore.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) X-Spam-Status: No, score=-4.3 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 16 Jun 2020 18:13:16 -0000 > I've now found where those are coming from: the thread name "gdb worker" > visible in ps -L provided the necessary clue. They are due to worker > threads now being enabled by default. On my desktop with 4 cores and > hyperthreading, that's relatively harmless. However, when I run gdb on > an 8-socket server with 160 cores total, the messages about thread > creation when debugging gdb are killing you ;-) I traced this to > maint.c (update_thread_pool_size) where the count defaults to > std::thread::hardware_concurrency (). Maybe a bit over-eager... Oh my.... I remember that this version of GDB makes parallel minimal reading the default. I think you can throttle down the number of threads using: maint set worker-threads N -- Joel