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 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 35885C433EF for ; Wed, 15 Jun 2022 09:34:16 +0000 (UTC) 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-441-dPLZNzLTOfaWI0j64s_i8Q-1; Wed, 15 Jun 2022 05:34:14 -0400 X-MC-Unique: dPLZNzLTOfaWI0j64s_i8Q-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 28928299E775; Wed, 15 Jun 2022 09:34:12 +0000 (UTC) Received: from mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (unknown [10.30.29.100]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5AADEC08F0D; Wed, 15 Jun 2022 09:34:07 +0000 (UTC) Received: from mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (localhost [IPv6:::1]) by mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (Postfix) with ESMTP id DF274194975A; Wed, 15 Jun 2022 09:34:06 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) by mm-prod-listman-01.mail-001.prod.us-east-1.aws.redhat.com (Postfix) with ESMTP id 225961947B84 for ; Wed, 15 Jun 2022 09:34:06 +0000 (UTC) Received: by smtp.corp.redhat.com (Postfix) id 07A26403350; Wed, 15 Jun 2022 09:34:06 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast10.extmail.prod.ext.rdu2.redhat.com [10.11.55.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 02B1240334F for ; Wed, 15 Jun 2022 09:34:05 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [205.139.110.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C0F951C13947 for ; Wed, 15 Jun 2022 09:34:05 +0000 (UTC) Received: from plutone.assyoma.it (host195-56-237-212.serverdedicati.aruba.it [212.237.56.195]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-82-WZpyN-JhMTSAS_a8762EDg-1; Wed, 15 Jun 2022 05:34:03 -0400 X-MC-Unique: WZpyN-JhMTSAS_a8762EDg-1 Received: from webmail.assyoma.it (localhost [IPv6:::1]) by plutone.assyoma.it (Postfix) with ESMTPA id BB41E1DEDC03; Wed, 15 Jun 2022 11:34:00 +0200 (CEST) MIME-Version: 1.0 Date: Wed, 15 Jun 2022 11:34:00 +0200 From: Gionatan Danti To: Zhiyong Ye In-Reply-To: References: <9c22b11a-b539-1974-7994-6835eea82bfd@bytedance.com> <8baee796-9bfb-47a8-1661-7e94437826c9@bytedance.com> <5970db8d-462f-0e35-741c-fa0fdc188fa2@bytedance.com> User-Agent: Roundcube Webmail/1.4.13 Message-ID: <31a7b7e9ea9e60fe42d93f6f113fcaf0@assyoma.it> X-Sender: g.danti@assyoma.it X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 2.85 on 10.11.54.10 Subject: Re: [linux-lvm] Why is the performance of my lvmthin snapshot so poor X-BeenThere: linux-lvm@redhat.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: LVM general discussion and development Cc: LVM general discussion and development Errors-To: linux-lvm-bounces@redhat.com Sender: "linux-lvm" X-Scanned-By: MIMEDefang 2.85 on 10.11.54.8 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=linux-lvm-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Il 2022-06-15 09:42 Zhiyong Ye ha scritto: > I regenerated the thin volume with the chunksize of 64K and the random > write performance data tested with fio 64k requests is as follows: > case iops > thin lv 9381 > snapshotted thin lv 8307 As expected, increasing I/O size (to avoid r/m/w) greatly reduced the issue (the ~11% hit is due to metadata allocation overhead). I don't see anything wrong, so I think you had to live with the previously recorded 10x performance hit when overwriting 4K blocks on a 64K chunk size thin volume... Regards. -- Danti Gionatan Supporto Tecnico Assyoma S.r.l. - www.assyoma.it email: g.danti@assyoma.it - info@assyoma.it GPG public key ID: FF5F32A8 _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://listman.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/