From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-x242.google.com (mail-pf0-x242.google.com [IPv6:2607:f8b0:400e:c00::242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id CB58C3B29E for ; Wed, 25 Jan 2017 16:48:49 -0500 (EST) Received: by mail-pf0-x242.google.com with SMTP id 19so15103276pfo.3 for ; Wed, 25 Jan 2017 13:48:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=message-id:subject:from:to:cc:date:in-reply-to:references :mime-version:content-transfer-encoding; bh=qOz2MKWYpiIVAoToLhJ28x9oxlRVI9cU8iqda8ZkOe4=; b=nvLGhQMcX+bPLTRyIFo70WbnlcE9pjFns7n//ROuM8iCaCCUF42cixPLoIYYgnFlGu Y+qRc3JvHWa/Rm6uzEOhKN6+wzUzoFEx6fb6jjDg9LNwWh2hRjT5pO7YLRu1oLss8v5k aV2a+kGXcXQbdcCLXBcZCPpyyELugoYCd8xgNpezKqqkuXjKXdpedKOWzhhmHNtVcixa YbBWvPWzfEynVw3faIWytmec4FKfEhcUiuA4r1WVrDF5JiKsxuKTuYuxz6O33pxDbYlm dxlTUF1bt1mnVDbhflIw5VvMSL8KugYBeSLee6Fh36HG7Ewc5aFgr9FQhK2uYNimCOat s4xg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:subject:from:to:cc:date:in-reply-to :references:mime-version:content-transfer-encoding; bh=qOz2MKWYpiIVAoToLhJ28x9oxlRVI9cU8iqda8ZkOe4=; b=Qo8Pe/s9pfqaM8/nqkzkkgGhWF3E2r98tD3+HQzHyMiDiD6iVzDki2uHO/7PcIAnWx 0PnfxZ3UYxGK4PnZDw6U4qBxq1BwROSObw0AitLd+AlPNgP2xOCwybSP9qCG4L7w4uVS kbDIViZo8IuQz6PBvO58trXUIO7ukwVjHS5OFzaRC3NmSmlYzcoY3pJrShnjPYHjrP8T OsHkZu6thuzjuQ3KoMF2hyQcmgZE+uTEMSo60o19MBNkUQKkD1Y5nEwdiIsPzVXMAnDb 0/SC5ycfgrk4ZQ16DHuW4/nShQjBwCFlMsbdyhMJTtOue6B2K4pT9bVMQriMasQywLXi Z6Dw== X-Gm-Message-State: AIkVDXKLKNX5+aAUnovHvuZ+tSI6l6dXzd3Z4EHUBQ+v6zTxfCEPPTP+rg8RFXzikT3cWg== X-Received: by 10.98.138.155 with SMTP id o27mr49227398pfk.113.1485380928851; Wed, 25 Jan 2017 13:48:48 -0800 (PST) Received: from ?IPv6:2620:0:1000:1704:901f:c554:68ed:6757? ([2620:0:1000:1704:901f:c554:68ed:6757]) by smtp.googlemail.com with ESMTPSA id a1sm3313372pgc.14.2017.01.25.13.48.48 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 25 Jan 2017 13:48:48 -0800 (PST) Message-ID: <1485380927.5145.61.camel@edumazet-glaptop3.roam.corp.google.com> From: Eric Dumazet To: Hans-Kristian Bakke Cc: Jonathan Morton , bloat@lists.bufferbloat.net Date: Wed, 25 Jan 2017 13:48:47 -0800 In-Reply-To: References: <58D7E8D3-5661-4126-80D9-2F2D4E478B10@gmail.com> <908CA0EF-3D84-4EB4-ABD8-3042668E842E@gmail.com> <8B89C257-99D4-4A9A-96ED-A103A2089A46@gmail.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4-0ubuntu2 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: Re: [Bloat] Initial tests with BBR in kernel 4.9 X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 25 Jan 2017 21:48:49 -0000 I do not know any particular issues with FQ in VM If you have a recent tc binary (iproute2 package) you can get some infos, as mentioned in this commit changelog : https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=fefa569a9d4bc4b7758c0fddd75bb0382c95da77 $ tc -s qd sh dev eth0 | grep latency 0 gc, 0 highprio, 32490767 throttled, 2382 ns latency On Wed, 2017-01-25 at 22:31 +0100, Hans-Kristian Bakke wrote: > kvm-clock is a paravirtualized clock that seems to use the CPUs TSC > capabilities if they exist. But it may not be perfect: > > > https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization_Host_Configuration_and_Guest_Installation_Guide/chap-Virtualization_Host_Configuration_and_Guest_Installation_Guide-KVM_guest_timing_management.html > > > On 25 January 2017 at 22:29, Hans-Kristian Bakke > wrote: > Actually I think that is because it may be using the newer > TSC: > dmesg | grep clocksource > [ 0.000000] clocksource: kvm-clock: mask: > 0xffffffffffffffff max_cycles: 0x1cd42e4dffb, max_idle_ns: > 881590591483 ns > [ 0.000000] clocksource: refined-jiffies: mask: 0xffffffff > max_cycles: 0xffffffff, max_idle_ns: 7645519600211568 ns > [ 0.000000] clocksource: hpet: mask: 0xffffffff max_cycles: > 0xffffffff, max_idle_ns: 19112604467 ns > [ 0.092665] clocksource: jiffies: mask: 0xffffffff > max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns > [ 0.366429] clocksource: Switched to clocksource kvm-clock > [ 0.378974] clocksource: acpi_pm: mask: 0xffffff > max_cycles: 0xffffff, max_idle_ns: 2085701024 ns > [ 1.666474] tsc: Refined TSC clocksource calibration: > 3200.013 MHz > [ 1.666479] clocksource: tsc: mask: 0xffffffffffffffff > max_cycles: 0x2e20562a1bb, max_idle_ns: 440795285529 ns > > > > On 25 January 2017 at 22:26, Jonathan Morton > wrote: > > > On 25 Jan, 2017, at 23:20, Hans-Kristian Bakke > wrote: > > > > ​[ 0.000000] ACPI: HPET 0x00000000BFFE274F 000038 > (v01 BOCHS BXPCHPET 00000001 BXPC 00000001) > > [ 0.000000] ACPI: HPET id: 0x8086a201 base: > 0xfed00000 > > [ 0.000000] clocksource: hpet: mask: 0xffffffff > max_cycles: 0xffffffff, max_idle_ns: 19112604467 ns > > [ 0.000000] hpet clockevent registered > > [ 0.362335] hpet0: at MMIO 0xfed00000, IRQs 2, 8, > 0 > > [ 0.362339] hpet0: 3 comparators, 64-bit > 100.000000 MHz counter > > [ 0.661731] rtc_cmos 00:00: alarms up to one day, > y3k, 114 bytes nvram, hpet irqs > > Conspicuously absent here is a line saying > “clocksource: Switched to clocksource hpet”. That may > be worth examining in more detail. > > - Jonathan Morton > > > > > > _______________________________________________ > Bloat mailing list > Bloat@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/bloat