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 [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id 455593858D28 for ; Thu, 22 Jun 2023 02:40:50 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 455593858D28 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=1687401649; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WC1xkw86Sg5c9kOC5Ltxpw2fupuQWsmvxVPJaQafP9Q=; b=M2OX4ZlYVLvR478BTbFUlHaR2opv0rplVFdrAyHXOcOEclfwUH0tu39EnDsStACDe1HPu4 lO4zXsikveTFoEBkk0jFb5KHrTnISkVINL86r/W0ztj/XdzcMHl6vcdGihowiAjoSiZyK+ eiTjtmDjURRiU+JXYGLc9GtnecTIlbY= 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-434-VR8v6xgZPziI1FUObH5NYg-1; Wed, 21 Jun 2023 22:40:46 -0400 X-MC-Unique: VR8v6xgZPziI1FUObH5NYg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6EE273C1014E; Thu, 22 Jun 2023 02:40:45 +0000 (UTC) Received: from redhat.com (unknown [10.22.32.43]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 46D531400C34; Thu, 22 Jun 2023 02:40:45 +0000 (UTC) Received: from fche by redhat.com with local (Exim 4.94.2) (envelope-from ) id 1qCAFY-0001Ob-8K; Wed, 21 Jun 2023 22:40:44 -0400 Date: Wed, 21 Jun 2023 22:40:44 -0400 From: "Frank Ch. Eigler" To: Romain GEISSLER Cc: Mark Wielaard , "elfutils-devel@sourceware.org" , Francois RIGAULT Subject: Re: Performance issue with systemd-coredump and container process linking 2000 shared libraries. Message-ID: <20230622024044.GI5772@redhat.com> References: <20230614133920.10-1-romain.geissler@amadeus.com> <20230620213701.GN24233@gnu.wildebeest.org> <754003F4-3708-4C9C-AA30-EB76DAECF059@amadeus.com> MIME-Version: 1.0 In-Reply-To: <754003F4-3708-4C9C-AA30-EB76DAECF059@amadeus.com> User-Agent: Mutt/1.12.0 (2019-05-25) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-7.7 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_H5,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE,TXREP,T_SCC_BODY_TEXT_LINE 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: Hi - > On our side Francois also told me this afternoon that he didn’t > really reproduce the same thing with my reproducer posted here and > the real systemd-coredump issue he witnessed live, and also noticed > that with DEBUGINFOD_URLS unset/set to the empty string my > reproducer has no problem anymore. [...] Just doing the math from the debuginfod-client point of view (ignoring other the later systemd side fix that moots this): For an application that processes these elf/dwarf files sequentially, queries for each synthetic solib are going to result in 2000 https-404 transactions, sans debuginfod caching. If you're lucky (reusing a dwfl object), elfutils may be able to reuse a long-lived https connection to a server, otherwise a new https connection might have to be spun up for each. But even with reuse, we're talking about 2000 pingponging messages. That will take a handful of minutes of elapsed time just by itself. If the calling code made these queries in parallel batches, it would be much faster overall. - FChE