Hugh Dickins <[email protected]> writes:
> LKP reports that v4.2 commit afa2db2fb6f1 ("tmpfs: truncate prealloc
> blocks past i_size") causes a 14.5% slowdown in the AIM9 creat-clo
> benchmark.
>
> creat-clo does just what you'd expect from the name, and creat's O_TRUNC
> on 0-length file does indeed get into more overhead now shmem_setattr()
> tests "0 <= 0" instead of "0 < 0".
>
> I'm not sure how much we care, but I think it would not be too VW-like
> to add in a check for whether any pages (or swap) are allocated: if none
> are allocated, there's none to remove from the radix_tree. At first I
> thought that check would be good enough for the unmaps too, but no: we
> should not skip the unlikely case of unmapping pages beyond the new EOF,
> which were COWed from holes which have now been reclaimed, leaving none.
>
> This gives me an 8.5% speedup: on Haswell instead of LKP's Westmere,
> and running a debug config before and after: I hope those account for
> the lesser speedup.
>
> And probably someone has a benchmark where a thousand threads keep on
> stat'ing the same file repeatedly: forestall that report by adjusting
> v4.3 commit 44a30220bc0a ("shmem: recalculate file inode when fstat")
> not to take the spinlock in shmem_getattr() when there's no work to do.
>
> Reported-by: Ying Huang <[email protected]>
> Signed-off-by: Hugh Dickins <[email protected]>
Hi, Hugh,
Thanks a lot for your support! The test on LKP shows that this patch
restores a big part of the regression! In following list,
c435a390574d012f8d30074135d8fcc6f480b484: is parent commit
afa2db2fb6f15f860069de94a1257db57589fe95: is the first bad commit has
performance regression.
43819159da2b77fedcf7562134d6003dccd6a068: is the fixing patch
=========================================================================================
compiler/cpufreq_governor/kconfig/rootfs/tbox_group/test/testcase/testtime:
gcc-4.9/performance/x86_64-rhel/debian-x86_64-2015-02-07.cgz/lkp-wsx02/creat-clo/aim9/300s
commit:
c435a390574d012f8d30074135d8fcc6f480b484
afa2db2fb6f15f860069de94a1257db57589fe95
43819159da2b77fedcf7562134d6003dccd6a068
c435a390574d012f afa2db2fb6f15f860069de94a1 43819159da2b77fedcf7562134
---------------- -------------------------- --------------------------
%stddev %change %stddev %change %stddev
\ | \ | \
563556 ± 1% -12.5% 493033 ± 5% -5.6% 531968 ± 1% aim9.creat-clo.ops_per_sec
11836 ± 7% +11.4% 13184 ± 7% +15.0% 13608 ± 5% numa-meminfo.node1.SReclaimable
10121526 ± 3% -12.1% 8897097 ± 5% -4.1% 9707953 ± 4% proc-vmstat.pgalloc_normal
9.34 ± 4% -11.4% 8.28 ± 3% -4.8% 8.88 ± 2% time.user_time
3480 ± 3% -2.5% 3395 ± 1% -28.5% 2488 ± 3% vmstat.system.cs
203275 ± 17% -6.8% 189453 ± 5% -34.4% 133352 ± 11% cpuidle.C1-NHM.usage
8081280 ±129% -93.3% 538377 ± 97% +31.5% 10625496 ±106% cpuidle.C1E-NHM.time
3144 ± 58% +619.0% 22606 ± 56% +903.9% 31563 ± 0% numa-vmstat.node0.numa_other
2958 ± 7% +11.4% 3295 ± 7% +15.0% 3401 ± 5% numa-vmstat.node1.nr_slab_reclaimable
45074 ± 5% -43.4% 25494 ± 57% -68.7% 14105 ± 2% numa-vmstat.node2.numa_other
56140 ± 0% +0.0% 56158 ± 0% -94.4% 3120 ± 0% slabinfo.Acpi-ParseExt.active_objs
1002 ± 0% +0.0% 1002 ± 0% -92.0% 80.00 ± 0% slabinfo.Acpi-ParseExt.active_slabs
56140 ± 0% +0.0% 56158 ± 0% -94.4% 3120 ± 0% slabinfo.Acpi-ParseExt.num_objs
1002 ± 0% +0.0% 1002 ± 0% -92.0% 80.00 ± 0% slabinfo.Acpi-ParseExt.num_slabs
1079 ± 5% -10.8% 962.00 ± 10% -100.0% 0.00 ± -1% slabinfo.blkdev_ioc.active_objs
1079 ± 5% -10.8% 962.00 ± 10% -100.0% 0.00 ± -1% slabinfo.blkdev_ioc.num_objs
110.67 ± 39% +74.4% 193.00 ± 46% +317.5% 462.00 ± 8% slabinfo.blkdev_queue.active_objs
189.33 ± 23% +43.7% 272.00 ± 33% +151.4% 476.00 ± 10% slabinfo.blkdev_queue.num_objs
1129 ± 10% -1.9% 1107 ± 7% +20.8% 1364 ± 6% slabinfo.blkdev_requests.active_objs
1129 ± 10% -1.9% 1107 ± 7% +20.8% 1364 ± 6% slabinfo.blkdev_requests.num_objs
1058 ± 3% -10.3% 949.00 ± 9% -100.0% 0.00 ± -1% slabinfo.file_lock_ctx.active_objs
1058 ± 3% -10.3% 949.00 ± 9% -100.0% 0.00 ± -1% slabinfo.file_lock_ctx.num_objs
4060 ± 1% -2.1% 3973 ± 1% -10.5% 3632 ± 1% slabinfo.files_cache.active_objs
4060 ± 1% -2.1% 3973 ± 1% -10.5% 3632 ± 1% slabinfo.files_cache.num_objs
10001 ± 0% -0.3% 9973 ± 0% -61.1% 3888 ± 0% slabinfo.ftrace_event_field.active_objs
10001 ± 0% -0.3% 9973 ± 0% -61.1% 3888 ± 0% slabinfo.ftrace_event_field.num_objs
1832 ± 0% +0.4% 1840 ± 0% -100.0% 0.00 ± -1% slabinfo.ftrace_event_file.active_objs
1832 ± 0% +0.4% 1840 ± 0% -100.0% 0.00 ± -1% slabinfo.ftrace_event_file.num_objs
1491 ± 5% -2.3% 1456 ± 6% +12.0% 1669 ± 4% slabinfo.mnt_cache.active_objs
1491 ± 5% -2.3% 1456 ± 6% +12.0% 1669 ± 4% slabinfo.mnt_cache.num_objs
126.33 ± 19% +10.2% 139.17 ± 9% -100.0% 0.00 ± -1% slabinfo.nfs_commit_data.active_objs
126.33 ± 19% +10.2% 139.17 ± 9% -100.0% 0.00 ± -1% slabinfo.nfs_commit_data.num_objs
97.17 ± 20% -9.1% 88.33 ± 28% -100.0% 0.00 ± -1% slabinfo.user_namespace.active_objs
97.17 ± 20% -9.1% 88.33 ± 28% -100.0% 0.00 ± -1% slabinfo.user_namespace.num_objs
Best Regards,
Huang, Ying
On Wed, 4 Nov 2015, Huang, Ying wrote:
> Hugh Dickins <[email protected]> writes:
>
> > LKP reports that v4.2 commit afa2db2fb6f1 ("tmpfs: truncate prealloc
> > blocks past i_size") causes a 14.5% slowdown in the AIM9 creat-clo
> > benchmark.
> >
> > creat-clo does just what you'd expect from the name, and creat's O_TRUNC
> > on 0-length file does indeed get into more overhead now shmem_setattr()
> > tests "0 <= 0" instead of "0 < 0".
> >
> > I'm not sure how much we care, but I think it would not be too VW-like
> > to add in a check for whether any pages (or swap) are allocated: if none
> > are allocated, there's none to remove from the radix_tree. At first I
> > thought that check would be good enough for the unmaps too, but no: we
> > should not skip the unlikely case of unmapping pages beyond the new EOF,
> > which were COWed from holes which have now been reclaimed, leaving none.
> >
> > This gives me an 8.5% speedup: on Haswell instead of LKP's Westmere,
> > and running a debug config before and after: I hope those account for
> > the lesser speedup.
> >
> > And probably someone has a benchmark where a thousand threads keep on
> > stat'ing the same file repeatedly: forestall that report by adjusting
> > v4.3 commit 44a30220bc0a ("shmem: recalculate file inode when fstat")
> > not to take the spinlock in shmem_getattr() when there's no work to do.
> >
> > Reported-by: Ying Huang <[email protected]>
> > Signed-off-by: Hugh Dickins <[email protected]>
>
> Hi, Hugh,
>
> Thanks a lot for your support! The test on LKP shows that this patch
> restores a big part of the regression! In following list,
>
> c435a390574d012f8d30074135d8fcc6f480b484: is parent commit
> afa2db2fb6f15f860069de94a1257db57589fe95: is the first bad commit has
> performance regression.
> 43819159da2b77fedcf7562134d6003dccd6a068: is the fixing patch
Hi Ying,
Thank you, for reporting, and for trying out the patch (which is now
in Linus's tree as commit d0424c429f8e0555a337d71e0a13f2289c636ec9).
But I'm disappointed by the result: do I understand correctly,
that afa2db2fb6f1 made a -12.5% change, but the fix still -5.6%
from your parent comparison point? If we value that microbenchmark
at all (debatable), I'd say that's not good enough.
It does match with my own rough measurement, but I'd been hoping
for better when done in a more controlled environment; and I cannot
explain why "truncate prealloc blocks past i_size" creat-clo performance
would not be fully corrected by "avoid a little creat and stat slowdown"
(unless either patch adds subtle icache or dcache displacements).
I'm not certain of how you performed the comparison. Was the
c435a390574d tree measured, then patch afa2db2fb6f1 applied on top
of that and measured, then patch 43819159da2b applied on top of that
and measured? Or were there other intervening changes, which could
easily add their own interference?
Hugh
>
> =========================================================================================
> compiler/cpufreq_governor/kconfig/rootfs/tbox_group/test/testcase/testtime:
> gcc-4.9/performance/x86_64-rhel/debian-x86_64-2015-02-07.cgz/lkp-wsx02/creat-clo/aim9/300s
>
> commit:
> c435a390574d012f8d30074135d8fcc6f480b484
> afa2db2fb6f15f860069de94a1257db57589fe95
> 43819159da2b77fedcf7562134d6003dccd6a068
>
> c435a390574d012f afa2db2fb6f15f860069de94a1 43819159da2b77fedcf7562134
> ---------------- -------------------------- --------------------------
> %stddev %change %stddev %change %stddev
> \ | \ | \
> 563556 ± 1% -12.5% 493033 ± 5% -5.6% 531968 ± 1% aim9.creat-clo.ops_per_sec
> 11836 ± 7% +11.4% 13184 ± 7% +15.0% 13608 ± 5% numa-meminfo.node1.SReclaimable
> 10121526 ± 3% -12.1% 8897097 ± 5% -4.1% 9707953 ± 4% proc-vmstat.pgalloc_normal
> 9.34 ± 4% -11.4% 8.28 ± 3% -4.8% 8.88 ± 2% time.user_time
> 3480 ± 3% -2.5% 3395 ± 1% -28.5% 2488 ± 3% vmstat.system.cs
> 203275 ± 17% -6.8% 189453 ± 5% -34.4% 133352 ± 11% cpuidle.C1-NHM.usage
> 8081280 ±129% -93.3% 538377 ± 97% +31.5% 10625496 ±106% cpuidle.C1E-NHM.time
> 3144 ± 58% +619.0% 22606 ± 56% +903.9% 31563 ± 0% numa-vmstat.node0.numa_other
> 2958 ± 7% +11.4% 3295 ± 7% +15.0% 3401 ± 5% numa-vmstat.node1.nr_slab_reclaimable
> 45074 ± 5% -43.4% 25494 ± 57% -68.7% 14105 ± 2% numa-vmstat.node2.numa_other
> 56140 ± 0% +0.0% 56158 ± 0% -94.4% 3120 ± 0% slabinfo.Acpi-ParseExt.active_objs
> 1002 ± 0% +0.0% 1002 ± 0% -92.0% 80.00 ± 0% slabinfo.Acpi-ParseExt.active_slabs
> 56140 ± 0% +0.0% 56158 ± 0% -94.4% 3120 ± 0% slabinfo.Acpi-ParseExt.num_objs
> 1002 ± 0% +0.0% 1002 ± 0% -92.0% 80.00 ± 0% slabinfo.Acpi-ParseExt.num_slabs
> 1079 ± 5% -10.8% 962.00 ± 10% -100.0% 0.00 ± -1% slabinfo.blkdev_ioc.active_objs
> 1079 ± 5% -10.8% 962.00 ± 10% -100.0% 0.00 ± -1% slabinfo.blkdev_ioc.num_objs
> 110.67 ± 39% +74.4% 193.00 ± 46% +317.5% 462.00 ± 8% slabinfo.blkdev_queue.active_objs
> 189.33 ± 23% +43.7% 272.00 ± 33% +151.4% 476.00 ± 10% slabinfo.blkdev_queue.num_objs
> 1129 ± 10% -1.9% 1107 ± 7% +20.8% 1364 ± 6% slabinfo.blkdev_requests.active_objs
> 1129 ± 10% -1.9% 1107 ± 7% +20.8% 1364 ± 6% slabinfo.blkdev_requests.num_objs
> 1058 ± 3% -10.3% 949.00 ± 9% -100.0% 0.00 ± -1% slabinfo.file_lock_ctx.active_objs
> 1058 ± 3% -10.3% 949.00 ± 9% -100.0% 0.00 ± -1% slabinfo.file_lock_ctx.num_objs
> 4060 ± 1% -2.1% 3973 ± 1% -10.5% 3632 ± 1% slabinfo.files_cache.active_objs
> 4060 ± 1% -2.1% 3973 ± 1% -10.5% 3632 ± 1% slabinfo.files_cache.num_objs
> 10001 ± 0% -0.3% 9973 ± 0% -61.1% 3888 ± 0% slabinfo.ftrace_event_field.active_objs
> 10001 ± 0% -0.3% 9973 ± 0% -61.1% 3888 ± 0% slabinfo.ftrace_event_field.num_objs
> 1832 ± 0% +0.4% 1840 ± 0% -100.0% 0.00 ± -1% slabinfo.ftrace_event_file.active_objs
> 1832 ± 0% +0.4% 1840 ± 0% -100.0% 0.00 ± -1% slabinfo.ftrace_event_file.num_objs
> 1491 ± 5% -2.3% 1456 ± 6% +12.0% 1669 ± 4% slabinfo.mnt_cache.active_objs
> 1491 ± 5% -2.3% 1456 ± 6% +12.0% 1669 ± 4% slabinfo.mnt_cache.num_objs
> 126.33 ± 19% +10.2% 139.17 ± 9% -100.0% 0.00 ± -1% slabinfo.nfs_commit_data.active_objs
> 126.33 ± 19% +10.2% 139.17 ± 9% -100.0% 0.00 ± -1% slabinfo.nfs_commit_data.num_objs
> 97.17 ± 20% -9.1% 88.33 ± 28% -100.0% 0.00 ± -1% slabinfo.user_namespace.active_objs
> 97.17 ± 20% -9.1% 88.33 ± 28% -100.0% 0.00 ± -1% slabinfo.user_namespace.num_objs
>
> Best Regards,
> Huang, Ying
Hugh Dickins <[email protected]> writes:
> On Wed, 4 Nov 2015, Huang, Ying wrote:
>> Hugh Dickins <[email protected]> writes:
>>
>> > LKP reports that v4.2 commit afa2db2fb6f1 ("tmpfs: truncate prealloc
>> > blocks past i_size") causes a 14.5% slowdown in the AIM9 creat-clo
>> > benchmark.
>> >
>> > creat-clo does just what you'd expect from the name, and creat's O_TRUNC
>> > on 0-length file does indeed get into more overhead now shmem_setattr()
>> > tests "0 <= 0" instead of "0 < 0".
>> >
>> > I'm not sure how much we care, but I think it would not be too VW-like
>> > to add in a check for whether any pages (or swap) are allocated: if none
>> > are allocated, there's none to remove from the radix_tree. At first I
>> > thought that check would be good enough for the unmaps too, but no: we
>> > should not skip the unlikely case of unmapping pages beyond the new EOF,
>> > which were COWed from holes which have now been reclaimed, leaving none.
>> >
>> > This gives me an 8.5% speedup: on Haswell instead of LKP's Westmere,
>> > and running a debug config before and after: I hope those account for
>> > the lesser speedup.
>> >
>> > And probably someone has a benchmark where a thousand threads keep on
>> > stat'ing the same file repeatedly: forestall that report by adjusting
>> > v4.3 commit 44a30220bc0a ("shmem: recalculate file inode when fstat")
>> > not to take the spinlock in shmem_getattr() when there's no work to do.
>> >
>> > Reported-by: Ying Huang <[email protected]>
>> > Signed-off-by: Hugh Dickins <[email protected]>
>>
>> Hi, Hugh,
>>
>> Thanks a lot for your support! The test on LKP shows that this patch
>> restores a big part of the regression! In following list,
>>
>> c435a390574d012f8d30074135d8fcc6f480b484: is parent commit
>> afa2db2fb6f15f860069de94a1257db57589fe95: is the first bad commit has
>> performance regression.
>> 43819159da2b77fedcf7562134d6003dccd6a068: is the fixing patch
>
> Hi Ying,
>
> Thank you, for reporting, and for trying out the patch (which is now
> in Linus's tree as commit d0424c429f8e0555a337d71e0a13f2289c636ec9).
>
> But I'm disappointed by the result: do I understand correctly,
> that afa2db2fb6f1 made a -12.5% change, but the fix still -5.6%
> from your parent comparison point?
Yes.
> If we value that microbenchmark
> at all (debatable), I'd say that's not good enough.
I think that is a good improvement.
> It does match with my own rough measurement, but I'd been hoping
> for better when done in a more controlled environment; and I cannot
> explain why "truncate prealloc blocks past i_size" creat-clo performance
> would not be fully corrected by "avoid a little creat and stat slowdown"
> (unless either patch adds subtle icache or dcache displacements).
>
> I'm not certain of how you performed the comparison. Was the
> c435a390574d tree measured, then patch afa2db2fb6f1 applied on top
> of that and measured, then patch 43819159da2b applied on top of that
> and measured? Or were there other intervening changes, which could
> easily add their own interference?
c435a390574d is the direct parent of afa2db2fb6f1 in its original git.
43819159da2b is your patch applied on top of v4.3-rc7. The comparison
of 43819159da2b with v4.3-rc7 is as follow:
=========================================================================================
compiler/cpufreq_governor/kconfig/rootfs/tbox_group/test/testcase/testtime:
gcc-4.9/performance/x86_64-rhel/debian-x86_64-2015-02-07.cgz/lkp-wsx02/creat-clo/aim9/300s
commit:
32b88194f71d6ae7768a29f87fbba454728273ee
43819159da2b77fedcf7562134d6003dccd6a068
32b88194f71d6ae7 43819159da2b77fedcf7562134
---------------- --------------------------
%stddev %change %stddev
\ | \
475224 ± 1% +11.9% 531968 ± 1% aim9.creat-clo.ops_per_sec
10469094 ±201% -52.3% 4998529 ±130% latency_stats.avg.nfs_wait_on_request.nfs_updatepage.nfs_write_end.generic_perform_write.__generic_file_write_iter.generic_file_write_iter.nfs_file_write.__vfs_write.vfs_write.SyS_write.entry_SYSCALL_64_fastpath
18852332 ±223% -73.5% 4998529 ±130% latency_stats.max.nfs_wait_on_request.nfs_updatepage.nfs_write_end.generic_perform_write.__generic_file_write_iter.generic_file_write_iter.nfs_file_write.__vfs_write.vfs_write.SyS_write.entry_SYSCALL_64_fastpath
21758590 ±199% -77.0% 4998529 ±130% latency_stats.sum.nfs_wait_on_request.nfs_updatepage.nfs_write_end.generic_perform_write.__generic_file_write_iter.generic_file_write_iter.nfs_file_write.__vfs_write.vfs_write.SyS_write.entry_SYSCALL_64_fastpath
4817724 ± 0% +9.6% 5280303 ± 1% proc-vmstat.numa_hit
4812582 ± 0% +9.7% 5280287 ± 1% proc-vmstat.numa_local
8499767 ± 4% +14.2% 9707953 ± 4% proc-vmstat.pgalloc_normal
8984075 ± 0% +10.4% 9919044 ± 1% proc-vmstat.pgfree
9.22 ± 8% +27.4% 11.75 ± 9% sched_debug.cfs_rq[0]:/.nr_spread_over
2667 ± 63% +90.0% 5068 ± 37% sched_debug.cfs_rq[20]:/.min_vruntime
152513 ±272% -98.5% 2306 ± 48% sched_debug.cfs_rq[21]:/.min_vruntime
477.36 ± 60% +128.6% 1091 ± 60% sched_debug.cfs_rq[27]:/.exec_clock
4.00 ±112% +418.8% 20.75 ± 67% sched_debug.cfs_rq[28]:/.util_avg
1212 ± 80% +195.0% 3577 ± 48% sched_debug.cfs_rq[29]:/.exec_clock
8119 ± 53% -60.4% 3217 ± 26% sched_debug.cfs_rq[2]:/.min_vruntime
584.80 ± 65% -60.0% 234.06 ± 13% sched_debug.cfs_rq[30]:/.exec_clock
4245 ± 27% -42.8% 2429 ± 24% sched_debug.cfs_rq[30]:/.min_vruntime
0.00 ± 0% +Inf% 2.25 ± 72% sched_debug.cfs_rq[44]:/.util_avg
1967 ± 39% +72.0% 3384 ± 15% sched_debug.cfs_rq[61]:/.min_vruntime
1863 ± 43% +99.2% 3710 ± 33% sched_debug.cfs_rq[72]:/.min_vruntime
0.78 ±336% -678.6% -4.50 ±-33% sched_debug.cpu#12.nr_uninterruptible
10686 ± 49% +77.8% 19002 ± 34% sched_debug.cpu#15.nr_switches
5256 ± 50% +79.0% 9410 ± 34% sched_debug.cpu#15.sched_goidle
-2.00 ±-139% -225.0% 2.50 ± 44% sched_debug.cpu#21.nr_uninterruptible
-1.78 ±-105% -156.2% 1.00 ±141% sched_debug.cpu#23.nr_uninterruptible
45017 ±132% -76.1% 10741 ± 30% sched_debug.cpu#24.nr_load_updates
2216 ± 14% +73.3% 3839 ± 63% sched_debug.cpu#35.nr_switches
2223 ± 14% +73.0% 3845 ± 63% sched_debug.cpu#35.sched_count
1030 ± 13% +79.1% 1845 ± 66% sched_debug.cpu#35.sched_goidle
2.00 ± 40% +37.5% 2.75 ± 82% sched_debug.cpu#46.nr_uninterruptible
907.11 ± 67% +403.7% 4569 ± 75% sched_debug.cpu#59.ttwu_count
-4.56 ±-41% -94.5% -0.25 ±-714% sched_debug.cpu#64.nr_uninterruptible
So you patch improved 11.9% from its base v4.3-rc7. I think other
difference are caused by other changes. Sorry for confusing.
Best Regards,
Huang, Ying
> Hugh
>
>>
>> =========================================================================================
>> compiler/cpufreq_governor/kconfig/rootfs/tbox_group/test/testcase/testtime:
>> gcc-4.9/performance/x86_64-rhel/debian-x86_64-2015-02-07.cgz/lkp-wsx02/creat-clo/aim9/300s
>>
>> commit:
>> c435a390574d012f8d30074135d8fcc6f480b484
>> afa2db2fb6f15f860069de94a1257db57589fe95
>> 43819159da2b77fedcf7562134d6003dccd6a068
>>
>> c435a390574d012f afa2db2fb6f15f860069de94a1 43819159da2b77fedcf7562134
>> ---------------- -------------------------- --------------------------
>> %stddev %change %stddev %change %stddev
>> \ | \ | \
>> 563556 ± 1% -12.5% 493033 ± 5% -5.6% 531968 ± 1% aim9.creat-clo.ops_per_sec
>> 11836 ± 7% +11.4% 13184 ± 7% +15.0% 13608 ± 5% numa-meminfo.node1.SReclaimable
>> 10121526 ± 3% -12.1% 8897097 ± 5% -4.1% 9707953 ± 4% proc-vmstat.pgalloc_normal
>> 9.34 ± 4% -11.4% 8.28 ± 3% -4.8% 8.88 ± 2% time.user_time
>> 3480 ± 3% -2.5% 3395 ± 1% -28.5% 2488 ± 3% vmstat.system.cs
>> 203275 ± 17% -6.8% 189453 ± 5% -34.4% 133352 ± 11% cpuidle.C1-NHM.usage
>> 8081280 ±129% -93.3% 538377 ± 97% +31.5% 10625496 ±106% cpuidle.C1E-NHM.time
>> 3144 ± 58% +619.0% 22606 ± 56% +903.9% 31563 ± 0% numa-vmstat.node0.numa_other
>> 2958 ± 7% +11.4% 3295 ± 7% +15.0% 3401 ± 5% numa-vmstat.node1.nr_slab_reclaimable
>> 45074 ± 5% -43.4% 25494 ± 57% -68.7% 14105 ± 2% numa-vmstat.node2.numa_other
>> 56140 ± 0% +0.0% 56158 ± 0% -94.4% 3120 ± 0% slabinfo.Acpi-ParseExt.active_objs
>> 1002 ± 0% +0.0% 1002 ± 0% -92.0% 80.00 ± 0% slabinfo.Acpi-ParseExt.active_slabs
>> 56140 ± 0% +0.0% 56158 ± 0% -94.4% 3120 ± 0% slabinfo.Acpi-ParseExt.num_objs
>> 1002 ± 0% +0.0% 1002 ± 0% -92.0% 80.00 ± 0% slabinfo.Acpi-ParseExt.num_slabs
>> 1079 ± 5% -10.8% 962.00 ± 10% -100.0% 0.00 ± -1% slabinfo.blkdev_ioc.active_objs
>> 1079 ± 5% -10.8% 962.00 ± 10% -100.0% 0.00 ± -1% slabinfo.blkdev_ioc.num_objs
>> 110.67 ± 39% +74.4% 193.00 ± 46% +317.5% 462.00 ± 8% slabinfo.blkdev_queue.active_objs
>> 189.33 ± 23% +43.7% 272.00 ± 33% +151.4% 476.00 ± 10% slabinfo.blkdev_queue.num_objs
>> 1129 ± 10% -1.9% 1107 ± 7% +20.8% 1364 ± 6% slabinfo.blkdev_requests.active_objs
>> 1129 ± 10% -1.9% 1107 ± 7% +20.8% 1364 ± 6% slabinfo.blkdev_requests.num_objs
>> 1058 ± 3% -10.3% 949.00 ± 9% -100.0% 0.00 ± -1% slabinfo.file_lock_ctx.active_objs
>> 1058 ± 3% -10.3% 949.00 ± 9% -100.0% 0.00 ± -1% slabinfo.file_lock_ctx.num_objs
>> 4060 ± 1% -2.1% 3973 ± 1% -10.5% 3632 ± 1% slabinfo.files_cache.active_objs
>> 4060 ± 1% -2.1% 3973 ± 1% -10.5% 3632 ± 1% slabinfo.files_cache.num_objs
>> 10001 ± 0% -0.3% 9973 ± 0% -61.1% 3888 ± 0% slabinfo.ftrace_event_field.active_objs
>> 10001 ± 0% -0.3% 9973 ± 0% -61.1% 3888 ± 0% slabinfo.ftrace_event_field.num_objs
>> 1832 ± 0% +0.4% 1840 ± 0% -100.0% 0.00 ± -1% slabinfo.ftrace_event_file.active_objs
>> 1832 ± 0% +0.4% 1840 ± 0% -100.0% 0.00 ± -1% slabinfo.ftrace_event_file.num_objs
>> 1491 ± 5% -2.3% 1456 ± 6% +12.0% 1669 ± 4% slabinfo.mnt_cache.active_objs
>> 1491 ± 5% -2.3% 1456 ± 6% +12.0% 1669 ± 4% slabinfo.mnt_cache.num_objs
>> 126.33 ± 19% +10.2% 139.17 ± 9% -100.0% 0.00 ± -1% slabinfo.nfs_commit_data.active_objs
>> 126.33 ± 19% +10.2% 139.17 ± 9% -100.0% 0.00 ± -1% slabinfo.nfs_commit_data.num_objs
>> 97.17 ± 20% -9.1% 88.33 ± 28% -100.0% 0.00 ± -1% slabinfo.user_namespace.active_objs
>> 97.17 ± 20% -9.1% 88.33 ± 28% -100.0% 0.00 ± -1% slabinfo.user_namespace.num_objs
>>
>> Best Regards,
>> Huang, Ying
On Fri, 13 Nov 2015, Huang, Ying wrote:
>
> c435a390574d is the direct parent of afa2db2fb6f1 in its original git.
> 43819159da2b is your patch applied on top of v4.3-rc7. The comparison
> of 43819159da2b with v4.3-rc7 is as follow:
...
> So you patch improved 11.9% from its base v4.3-rc7. I think other
> difference are caused by other changes. Sorry for confusing.
Thanks for getting back on this: that's rather what I was hoping to hear.
Of course, no user will care which commit is responsible for a slowdown,
and we may need to look further; but I couldn't make sense of it before,
so this was a relief.
Hugh