From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33069) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cIzSY-00047S-Lq for qemu-devel@nongnu.org; Mon, 19 Dec 2016 10:02:42 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cIzST-0003vP-7B for qemu-devel@nongnu.org; Mon, 19 Dec 2016 10:02:38 -0500 Received: from mail-wm0-x241.google.com ([2a00:1450:400c:c09::241]:36203) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1cIzST-0003v8-1a for qemu-devel@nongnu.org; Mon, 19 Dec 2016 10:02:33 -0500 Received: by mail-wm0-x241.google.com with SMTP id m203so19070919wma.3 for ; Mon, 19 Dec 2016 07:02:32 -0800 (PST) Date: Mon, 19 Dec 2016 15:02:30 +0000 From: Stefan Hajnoczi Message-ID: <20161219150230.GA20757@stefanha-x1.localdomain> References: <1482137486-9843-1-git-send-email-douly.fnst@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="jRHKVT23PllUwdXP" Content-Disposition: inline In-Reply-To: <1482137486-9843-1-git-send-email-douly.fnst@cn.fujitsu.com> Subject: Re: [Qemu-devel] [PATCH RFC v2 0/4] block/qapi: refactor and optimize the qmp_query_blockstats() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Dou Liyang Cc: stefanha@redhat.com, kwolf@redhat.com, armbru@redhat.com, mreitz@redhat.com, eblake@redhat.com, famz@redhat.com, danpb@redhat.com, izumi.taku@jp.fujitsu.com, caoj.fnst@cn.fujitsu.com, fanc.fnst@cn.fujitsu.com, qemu-devel@nongnu.org --jRHKVT23PllUwdXP Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Dec 19, 2016 at 04:51:22PM +0800, Dou Liyang wrote: > These patches aim to refactor the qmp_query_blockstats() and > improve the performance by reducing the running time of it. >=20 > qmp_query_blockstats() is used to monitor the blockstats, it > querys all the graph_bdrv_states or monitor_block_backends. >=20 > There are the two jobs: >=20 > 1 For the performance: >=20 > 1.1 the time it takes(ns) in each time: > the disk numbers | 10 | 500 > ------------------------------------- > before these patches | 19429 | 667722=20 > after these patches | 17516 | 557044 >=20 > 1.2 the I/O performance is degraded(%) during the monitor: >=20 > the disk numbers | 10 | 500 > ------------------------------------- > before these patches | 1.3 | 14.2 > after these patches | 0.8 | 9.1 Do you know what is consuming the remaining 9.1%? I'm surprised to see such a high performance impact caused by a QMP command. Please post your QEMU command-line. --jRHKVT23PllUwdXP Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEcBAEBAgAGBQJYV/aGAAoJEJykq7OBq3PIvqcIAKM8gPmMGCWzu3WRBszavK6k g4Vwt1HEuheEHOcK8baPpW1MRrSW/H3mbGZ+Fj3alapT7k6fXISXgufQlzrA7+eo tg5vbwGcruGAOiP9EpRR1K2QtoUsFVZ17tWy+nZV/1+CS89+eBP5FsPl/AXqn7IF QsuGE2gTVdjw0d808tC/5U84963gfcFhIaSo6gWSL/jKH47R5E+LmJSdJMPhcuVE wxmuJZ7Lf5mNfOx2Yx34KrKPNQ9n1QI6H88RRVouyIl6WDGNyIArhRsvtm0fxArs jp6TUQWUGoJthlOkcLZC2nbPH2LOsqnZSs0A/tZ1u0ml3xNy58afZgXuAJtZmY4= =UT45 -----END PGP SIGNATURE----- --jRHKVT23PllUwdXP--