From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35417) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YG8mv-0000AA-91 for qemu-devel@nongnu.org; Tue, 27 Jan 2015 11:14:50 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YG8mp-0002ry-HO for qemu-devel@nongnu.org; Tue, 27 Jan 2015 11:14:49 -0500 Received: from mx1.redhat.com ([209.132.183.28]:50476) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YG8mp-0002rm-Au for qemu-devel@nongnu.org; Tue, 27 Jan 2015 11:14:43 -0500 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id t0RGEg94005369 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Tue, 27 Jan 2015 11:14:42 -0500 Message-ID: <54C7B970.5080002@redhat.com> Date: Tue, 27 Jan 2015 11:14:40 -0500 From: Max Reitz MIME-Version: 1.0 References: <1421397983-28065-1-git-send-email-famz@redhat.com> <1421397983-28065-6-git-send-email-famz@redhat.com> <54C6A773.1090903@redhat.com> <20150127030331.GB7715@fam-t430.nay.redhat.com> In-Reply-To: <20150127030331.GB7715@fam-t430.nay.redhat.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v5 5/5] qemu-iotests: Add 093 for IO throttling List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Fam Zheng Cc: Kevin Wolf , qemu-devel@nongnu.org, Stefan Hajnoczi On 2015-01-26 at 22:03, Fam Zheng wrote: > On Mon, 01/26 15:45, Max Reitz wrote: >> On 2015-01-16 at 03:46, Fam Zheng wrote: >>> This case utilizes qemu-io command "aio_{read,write} -q" to verify the >>> effectiveness of IO throttling options. >>> >>> It's implemented by driving the vm timer from qtest protocol, so the >>> throttling timers are signaled with determinied time duration. Then we >>> verify the completed IO requests are within 10% error of bps and iops >>> limits. >>> >>> "null" protocol is used as the disk backend so that no actual disk IO is >>> performed on host, this will make the blockstats much more >>> deterministic. Both "null-aio" and "null-co" are covered, which is also >>> a simple cross validation test for the driver code. >>> >>> Signed-off-by: Fam Zheng >>> --- >>> tests/qemu-iotests/093 | 103 +++++++++++++++++++++++++++++++++++++++++++++ >>> tests/qemu-iotests/093.out | 5 +++ >>> tests/qemu-iotests/group | 1 + >>> 3 files changed, 109 insertions(+) >>> create mode 100755 tests/qemu-iotests/093 >>> create mode 100644 tests/qemu-iotests/093.out >> NACK. This literally kills my laptop (I can recover when running this test >> in tmpfs (for some reason inexplicable to me, since this uses the null block >> drivers...), but I cannot when running it on my HDD). >> >> Would it be possible to use larger requests and smaller iops? (Or just the >> same request size but smaller bps as well) > Is it because of CPU or memory? 1000 requests for both read and write seem to > be overkilling since we are measuring 1000 bps and 10 iops, please try if > reducing to 100 requests works for you. Probably memory, since I seem to recall you having the same model as me, but I can imagine you having more RAM... 100 requests do not work with 128,000 bps/64 iops/10 seconds (because that'd be more than 1 MB of data, whereas 100 requests of 4 kB are of course only 400 kB), but the following constellations work: - 100 requests/128,000 bps/64 iops/1 second - 100 requests/26,214 bps/8 iops/10 seconds (26,214 is about one tenth of 262,144 which is a multiple of 4,096, so the real value will not be too far off; the iops are limited by $number_of_requests / $duration_in_seconds) I just hope there won't be some other poor guy for whom even this is too much... Max >> PS: Feel free to tell me I'm doing something wrong, of course. But just >> ./check -T -raw -c writethrough 093 just killed my laptop, and simply >> ./check -raw 093 would have probably killed it, too, if I wouldn't have held >> down ^C after some seconds (I'm listening to music and that's when it began >> stuttering...). >> >>> diff --git a/tests/qemu-iotests/093 b/tests/qemu-iotests/093 >>> new file mode 100755 >>> index 0000000..d12cc25 >>> --- /dev/null >>> +++ b/tests/qemu-iotests/093 >>> @@ -0,0 +1,103 @@ >>> +#!/usr/bin/env python >>> +# >>> +# Tests for IO throttling >>> +# >>> +# Copyright (C) 2015 Red Hat, Inc. >>> +# >>> +# This program is free software; you can redistribute it and/or modify >>> +# it under the terms of the GNU General Public License as published by >>> +# the Free Software Foundation; either version 2 of the License, or >>> +# (at your option) any later version. >>> +# >>> +# This program is distributed in the hope that it will be useful, >>> +# but WITHOUT ANY WARRANTY; without even the implied warranty of >>> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >>> +# GNU General Public License for more details. >>> +# >>> +# You should have received a copy of the GNU General Public License >>> +# along with this program. If not, see . >>> +# >>> + >>> +import iotests >>> + >>> +class ThrottleTestCase(iotests.QMPTestCase): >>> + test_img = "null-aio://" >>> + >>> + def blockstats(self, device): >>> + result = self.vm.qmp("query-blockstats") >>> + for r in result['return']: >>> + if r['device'] == device: >>> + stat = r['stats'] >>> + return stat['rd_bytes'], stat['rd_operations'], stat['wr_bytes'], stat['wr_operations'] >>> + raise Exception("Device not found for blockstats: %s" % device) >>> + >>> + def setUp(self): >>> + self.vm = iotests.VM().add_drive(self.test_img) >>> + self.vm.launch() >>> + >>> + def tearDown(self): >>> + self.vm.shutdown() >>> + >>> + def do_test_throttle(self, seconds, params): >>> + def check_limit(limit, num): >>> + # IO throttling algorithm is discrete, allow 10% error so the test >>> + # is more >> "more robust"? > Yes :) > > Fam