On 17/06/2020 16:52, Peter Puhov wrote:
> On Wed, 17 Jun 2020 at 06:50, Valentin Schneider
> <[email protected]> wrote:
>>
>>
>> On 16/06/20 17:48, [email protected] wrote:
>>> From: Peter Puhov <[email protected]>
>>> We tested this patch with following benchmarks:
>>> perf bench -f simple sched pipe -l 4000000
>>> perf bench -f simple sched messaging -l 30000
>>> perf bench -f simple mem memset -s 3GB -l 15 -f default
>>> perf bench -f simple futex wake -s -t 640 -w 1
>>> sysbench cpu --threads=8 --cpu-max-prime=10000 run
>>> sysbench memory --memory-access-mode=rnd --threads=8 run
>>> sysbench threads --threads=8 run
>>> sysbench mutex --mutex-num=1 --threads=8 run
>>> hackbench --loops 20000
>>> hackbench --pipe --threads --loops 20000
>>> hackbench --pipe --threads --loops 20000 --datasize 4096
>>>
>>> and found some performance improvements in:
>>> sysbench threads
>>> sysbench mutex
>>> perf bench futex wake
>>> and no regressions in others.
>>>
>>
>> One nitpick for the results of those: condensing them in a table form would
>> make them more reader-friendly. Perhaps something like:
>>
>> | Benchmark | Metric | Lower is better? | BASELINE | SERIES | DELTA
>> |
>> |------------------+----------+------------------+----------+--------+-------|
>> | Sysbench threads | # events | No | 45526 | 56567 | +24%
>> |
>> | Sysbench mutex | ... | | | |
>> |
>>
>> If you want to include more stats for each benchmark, you could have one
>> table
>> per (e.g. see [1]) - it'd still be a more readable form (or so I believe).
Wouldn't Unix Bench's 'execl' and 'spawn' be the ultimate test cases
for those kind of changes?
I only see minor improvements with tip/sched/core as base on hikey620
(Arm64 octa-core).
base w/ patch
./Run spawn -c 8 -i 10 633.6 635.1
./Run execl -c 8 -i 10 1187.5 1190.7
At the end of find_idlest_group(), when comparing local and idlest, it
is explicitly mentioned that number of idle_cpus is used instead of
utilization.
The comparision between potential idle groups and local & idlest group
should probably follow the same rules.
I haven't tested it with
https://lkml.kernel.org/r/[email protected]
which might have an influence here too.