Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755338Ab3HWJA0 (ORCPT ); Fri, 23 Aug 2013 05:00:26 -0400 Received: from fold.natur.cuni.cz ([195.113.57.32]:50879 "EHLO fold.natur.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754840Ab3HWJAX (ORCPT ); Fri, 23 Aug 2013 05:00:23 -0400 X-Greylist: delayed 486 seconds by postgrey-1.27 at vger.kernel.org; Fri, 23 Aug 2013 05:00:23 EDT Message-ID: <521722EE.70209@fold.natur.cuni.cz> Date: Fri, 23 Aug 2013 10:53:02 +0200 From: Martin Mokrejs User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:23.0) Gecko/20100101 Firefox/23.0 SeaMonkey/2.20 MIME-Version: 1.0 To: Theodore Tso , Thomas Gleixner , mingo@redhat.com, peterz@infradead.org CC: LKML Subject: [sched_delayed] sched: RT throttling activated X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5491 Lines: 113 Hi, I tried to figure out what this message really means. I came to https://rt.wiki.kernel.org/index.php/Frequently_Asked_Questions but I am still lost. I lack in the FAQ some user-related information. The first paragraph is still unclear to me. I have a i7-2640M based laptop, hyperthreading is enabled by BIOS but I shut down the two emulated cores by (no BIOS option to disable HT): echo 0 > /sys/devices/system/cpu/cpu2/online echo 0 > /sys/devices/system/cpu/cpu3/online At least I hope I shutdown those emulated ones. i7z claims I did the right thing and IntelPerformanceCounterMonitorV2.5.1/pcm.x application says the same: EXEC : instructions per nominal CPU cycle IPC : instructions per CPU cycle FREQ : relation to nominal CPU frequency='unhalted clock ticks'/'invariant timer ticks' (includes Intel Turbo Boost) AFREQ : relation to nominal CPU frequency while in active state (not in power-saving C state)='unhalted clock ticks'/'invariant timer ticks while in C0-state' (includes Intel Turbo Boost) L3MISS: L3 cache misses L2MISS: L2 cache misses (including other core's L2 cache *hits*) L3HIT : L3 cache hit ratio (0.00-1.00) L2HIT : L2 cache hit ratio (0.00-1.00) L3CLK : ratio of CPU cycles lost due to L3 cache misses (0.00-1.00), in some cases could be >1.0 due to a higher memory latency L2CLK : ratio of CPU cycles lost due to missing L2 cache but still hitting L3 cache (0.00-1.00) READ : bytes read from memory controller (in GBytes) WRITE : bytes written to memory controller (in GBytes) TEMP : Temperature reading in 1 degree Celsius relative to the TjMax temperature (thermal headroom): 0 corresponds to the max temperature Core (SKT) | EXEC | IPC | FREQ | AFREQ | L3MISS | L2MISS | L3HIT | L2HIT | L3CLK | L2CLK | READ | WRITE | TEMP 0 0 1.78 1.51 1.18 1.18 1595 K 3363 K 0.53 0.00 0.09 0.02 N/A N/A 23 1 0 1.21 1.03 1.18 1.18 9359 K 13 M 0.31 0.00 0.51 0.04 N/A N/A 24 ------------------------------------------------------------------------------------------------------------------- SKT 0 1.50 1.27 1.18 1.18 10 M 16 M 0.35 0.00 0.30 0.03 1.32 0.37 24 ------------------------------------------------------------------------------------------------------------------- TOTAL * 1.50 1.27 1.18 1.18 10 M 16 M 0.35 0.00 0.30 0.03 1.32 0.37 N/A Instructions retired: 8368 M ; Active cycles: 6594 M ; Time (TSC): 2797 Mticks ; C0 (active,non-halted) core residency: 100.00 % C1 core residency: 0.00 %; C3 core residency: 0.00 %; C6 core residency: 0.00 %; C7 core residency: 0.00 % C2 package residency: 0.00 %; C3 package residency: 0.00 %; C6 package residency: 0.00 %; C7 package residency: 0.00 % PHYSICAL CORE IPC : 1.27 => corresponds to 31.73 % utilization for cores in active state Instructions per nominal CPU cycle: 1.50 => corresponds to 37.40 % core utilization over time interval ---------------------------------------------------------------------------------------------- ---------------------------------------------------------------------------------------------- SKT 0 package consumed 28.18 Joules ---------------------------------------------------------------------------------------------- TOTAL: 28.18 Joules Why do I get the message at all? I have in 3.10.9 kernel: ... CONFIG_IOSCHED_DEADLINE=y CONFIG_DEFAULT_IOSCHED="deadline" ... CONFIG_NR_CPUS=4 ... # CONFIG_PREEMPT_RCU is not set CONFIG_PREEMPT_NONE=y # CONFIG_PREEMPT_VOLUNTARY is not set # CONFIG_PREEMPT is not set ... # CONFIG_SCHED_MC is not set CONFIG_SCHED_HRTICK=y I fear this is about CPU being overloaded (both cores loaded by user processes), by why do I get the message at all? Cpu speed from cpuinfo 2796.00Mhz cpuinfo might be wrong if cpufreq is enabled. To guess correctly try estimating via tsc Linux's inbuilt cpu_khz code emulated now True Frequency (without accounting Turbo) 2796 MHz CPU Multiplier 28x || Bus clock frequency (BCLK) 99.86 MHz Socket [0] - [physical cores=2, logical cores=2, max online cores ever=2] TURBO ENABLED on 2 Cores, Hyper Threading OFF Max Frequency without considering Turbo 2895.86 MHz (99.86 x [29]) Max TURBO Multiplier (if Enabled) with 1/2/3/4 Cores is 35x/33x/33x/33x Real Current Frequency 3295.29 MHz [99.86 x 33.00] (Max of below) Core [core-id] :Actual Freq (Mult.) C0% Halt(C1)% C3 % C6 % C7 % Temp Core 1 [0]: 3295.28 (33.00x) 100 0 0 0 0 76 Core 2 [1]: 3295.29 (33.00x) 100 0 0 0 0 76 Would you please clarify what the "[sched_delayed] sched: RT throttling activated" really means? Is that because there is some RT-requiring application on my system? I don't know of any (or don't care about real-time responsiveness except that ALSA drivers require me to have CONFIG_SND_HRTIMER=y). Per Goggle answers could the culprit be nfsd? Then I will recompile is as a module. # ps -ef | grep nfs root 920 2 0 Aug22 ? 00:00:00 [nfsiod] # Thank you, Martin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/