Messages in this thread | | | Date | Wed, 25 Dec 2013 14:32:07 +0800 | From | Alex Shi <> | Subject | Re: [sched] perf-stat.cpu-migrations changes in dd write test |
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On 12/25/2013 11:56 AM, Fengguang Wu wrote: > On Wed, Dec 25, 2013 at 11:30:27AM +0800, Alex Shi wrote: >> On 12/23/2013 01:24 PM, Fengguang Wu wrote: >>> On Mon, Dec 23, 2013 at 01:19:04PM +0800, Alex Shi wrote: >>>> On 12/22/2013 08:30 AM, fengguang.wu@intel.com wrote: >>>>> Alex, >>>>> >>>>> We noticed some perf-stat.cpu-migrations changes by your commit >>>> >>>> Thanks for your wonder testing, Fengguang! >>>> How many CPU in your system and how many dd task running? >>> >>> For the case >>> >>> kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd >>> >>> It's a KVM with 4 CPUs, 16G memory. There are 4 virtual disks, on top >>> of each disk there runs 10 dd tasks. >> >> I don't know much of kvm. Where the data get from, VM guest or VM host? > > The data are collected in the VM guest.
do you have similar testing on native linux? > > Thanks, > Fengguang > >> Looks like any guest cpu usage will be counted as user usage in vmstat. >> and Does the CS and cpu migration reducing cause dd performance increase? >>> >>> Thanks, >>> Fengguang >>> >>>>> >>>>> 6eb8b571283e64e96ca1a91aad085f9e08f857f0 is the first bad commit >>>>> commit 6eb8b571283e64e96ca1a91aad085f9e08f857f0 >>>>> Author: Alex Shi <alex.shi@linaro.org> >>>>> Date: Tue Nov 19 20:29:51 2013 +0800 >>>>> >>>>> sched: remove rq->cpu_load[load_idx] array >>>>> >>>>> Since load_idx effect removed in load balance, we don't need the >>>>> load_idx decays in scheduler. that will save some process in sched_tick >>>>> and others places. >>>>> >>>>> Signed-off-by: Alex Shi <alex.shi@linaro.org> >>>>> >>>>> >>>>> Here are the changed stats comparing to its parent commit: >>>>> >>>>> 1de157d718f6494 6eb8b571283e64e96ca1 >>>>> --------------- ------------------------- >>>>> 37779 ~40% +115.2% 81288 ~50% kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd >>>>> 37779 +115.2% 81288 TOTAL proc-vmstat.pgscan_direct_normal >>>>> >>>>> kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd: proc-vmstat.pgscan_direct_normal >>>>> >>>>> 160000 ++----------------------------------------------------------------+ >>>>> | | >>>>> 140000 ++ O >>>>> | | >>>>> 120000 ++ | >>>>> | O | >>>>> 100000 ++ | >>>>> | | >>>>> 80000 ++ O | >>>>> | ..* >>>>> 60000 ++ .... | >>>>> | .... | >>>>> 40000 *+............... O .... | >>>>> O *............... ........*. | >>>>> 20000 ++-------------------------------*--------------------------------+ >>>>> >>>>> >>>>> 1de157d718f6494 6eb8b571283e64e96ca1 >>>>> --------------- ------------------------- >>>>> 121579 ~ 6% -50.8% 59852 ~13% kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd >>>>> 121579 -50.8% 59852 TOTAL softirqs.SCHED >>>>> >>>>> kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd: softirqs.SCHED >>>>> >>>>> 140000 ++----------------------------------------------------------------+ >>>>> 130000 ++ ....*........... ....*....... | >>>>> | ........ .... ........ ...... | >>>>> 120000 *+... *.... ..| >>>>> 110000 ++ * >>>>> | | >>>>> 100000 ++ | >>>>> 90000 ++ | >>>>> 80000 ++ | >>>>> | | >>>>> 70000 ++ O O | >>>>> 60000 ++ O | >>>>> | O >>>>> 50000 O+ | >>>>> 40000 ++----------------------------------------------------------------+ >>>>> >>>>> >>>>> 1de157d718f6494 6eb8b571283e64e96ca1 >>>>> --------------- ------------------------- >>>>> 5636 ~ 4% -22.1% 4392 ~17% kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd >>>>> 5636 -22.1% 4392 TOTAL proc-vmstat.nr_tlb_remote_flush >>>>> >>>>> kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd: proc-vmstat.nr_tlb_remote_flush >>>>> >>>>> 6500 ++------------------------------------------------------------------+ >>>>> | | >>>>> 6000 ++ ........*............ | >>>>> *........ .... | >>>>> 5500 ++ O *................*................| >>>>> | * >>>>> 5000 ++ O | >>>>> | | >>>>> 4500 ++ O | >>>>> | | >>>>> 4000 ++ | >>>>> | O >>>>> 3500 O+ | >>>>> | | >>>>> 3000 ++------------------------------------------------------------------+ >>>>> >>>>> >>>>> 1de157d718f6494 6eb8b571283e64e96ca1 >>>>> --------------- ------------------------- >>>>> 5679 ~ 4% -21.9% 4437 ~17% kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd >>>>> 5679 -21.9% 4437 TOTAL proc-vmstat.nr_tlb_remote_flush_received >>>>> >>>>> >>>>> >>>>> 6500 ++------------------------------------------------------------------+ >>>>> | | >>>>> 6000 ++ ........*........ | >>>>> *........ ...... | >>>>> | .. ........*................| >>>>> 5500 ++ O *........ * >>>>> | | >>>>> 5000 ++ O | >>>>> | | >>>>> 4500 ++ O | >>>>> | | >>>>> | | >>>>> 4000 ++ | >>>>> | O >>>>> 3500 O+------------------------------------------------------------------+ >>>>> >>>>> >>>>> 1de157d718f6494 6eb8b571283e64e96ca1 >>>>> --------------- ------------------------- >>>>> 167 ~11% +19.4% 200 ~ 4% kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd >>>>> 167 +19.4% 200 TOTAL uptime.idle >>>>> >>>>> kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd: uptime.idle >>>>> >>>>> 220 ++-------------------------------------------------------------------+ >>>>> | O >>>>> 210 ++ | >>>>> 200 O+ O | >>>>> | ..*..... O | >>>>> 190 ++ .... O ... | >>>>> 180 ++ .... .... | >>>>> | .... .... | >>>>> 170 *+. . .* >>>>> 160 ++ *...... .... | >>>>> | .... ... | >>>>> 150 ++ .... ... | >>>>> 140 ++ .. .... | >>>>> | *. | >>>>> 130 ++-------------------------------------------------------------------+ >>>>> >>>>> >>>>> 1de157d718f6494 6eb8b571283e64e96ca1 >>>>> --------------- ------------------------- >>>>> 154781 ~ 5% -66.8% 51449 ~ 8% kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd >>>>> 154781 -66.8% 51449 TOTAL perf-stat.cpu-migrations >>>>> >>>>> kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd: perf-stat.cpu-migrations >>>>> >>>>> 180000 ++----------------------------------------------------------------+ >>>>> | ....*........... | >>>>> 160000 ++ ........ .... ........*...............| >>>>> *.... *........ * >>>>> 140000 ++ | >>>>> | | >>>>> 120000 ++ | >>>>> | | >>>>> 100000 ++ | >>>>> | | >>>>> 80000 ++ | >>>>> | | >>>>> 60000 ++ O | >>>>> | O O O >>>>> 40000 O+----------------------------------------------------------------+ >>>>> >>>>> >>>>> 1de157d718f6494 6eb8b571283e64e96ca1 >>>>> --------------- ------------------------- >>>>> 1943 ~ 3% -7.8% 1792 ~ 4% kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd >>>>> 1943 -7.8% 1792 TOTAL vmstat.system.cs >>>>> >>>>> kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd: vmstat.system.cs >>>>> >>>>> 2050 ++------------------------------------------------------------------+ >>>>> | ........*................*..... | >>>>> 2000 ++ .*........ ... | >>>>> 1950 ++ .... ... | >>>>> | ... .... | >>>>> 1900 ++ ... .| >>>>> 1850 ++.... O O * >>>>> *. | >>>>> 1800 ++ O O >>>>> 1750 ++ | >>>>> | | >>>>> 1700 ++ | >>>>> 1650 O+ | >>>>> | | >>>>> 1600 ++------------------------------------------------------------------+ >>>>> >>>>> >>>>> 1de157d718f6494 6eb8b571283e64e96ca1 >>>>> --------------- ------------------------- >>>>> 1216177 ~ 3% -9.4% 1101605 ~ 7% kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd >>>>> 1216177 -9.4% 1101605 TOTAL perf-stat.context-switches >>>>> >>>>> kbuildx/micro/dd-write/4HDD-JBOD-cfq-ext4-10dd: perf-stat.context-switches >>>>> >>>>> 1.3e+06 ++--------------------------------------------------------------+ >>>>> | ..*............... | >>>>> 1.25e+06 ++ ...... *...............*....... | >>>>> | ..... ...... | >>>>> 1.2e+06 *+. O ..| >>>>> 1.15e+06 ++ O * >>>>> | O | >>>>> 1.1e+06 ++ | >>>>> | O >>>>> 1.05e+06 ++ | >>>>> 1e+06 ++ | >>>>> | | >>>>> 950000 O+ | >>>>> | | >>>>> 900000 ++--------------------------------------------------------------+ >>>>> >>>>> >>>> >>>> >>>> -- >>>> Thanks >>>> Alex >> >> >> -- >> Thanks >> Alex
-- Thanks Alex
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