Re: [PATCH -mm -V3 00/21] mm, THP, swap: Swapout/swapin THP in one piece

[Huang\, Ying]

Daniel Jordan <daniel.m.jordan@xxxxxxxxxx> writes:

> On Wed, May 23, 2018 at 04:26:04PM +0800, Huang, Ying wrote:
>> And for all, Any comment is welcome!
>> 
>> This patchset is based on the 2018-05-18 head of mmotm/master.
>
> Trying to review this and it doesn't apply to mmotm-2018-05-18-16-44.  git
> fails on patch 10:
>
> Applying: mm, THP, swap: Support to count THP swapin and its fallback
> error: Documentation/vm/transhuge.rst: does not exist in index
> Patch failed at 0010 mm, THP, swap: Support to count THP swapin and its fallback
>
> Sure enough, this tag has Documentation/vm/transhuge.txt but not the .rst
> version.  Was this the tag you meant?  If so did you pull in some of Mike
> Rapoport's doc changes on top?

I use the mmotm tree at

git://git.cmpxchg.org/linux-mmotm.git

Maybe you are using the other one?

>>             base                  optimized
>> ---------------- -------------------------- 
>>          %stddev     %change         %stddev
>>              \          |                \  
>>    1417897   2%    +992.8%   15494673        vm-scalability.throughput
>>    1020489   4%   +1091.2%   12156349        vmstat.swap.si
>>    1255093   3%    +940.3%   13056114        vmstat.swap.so
>>    1259769   7%   +1818.3%   24166779        meminfo.AnonHugePages
>>   28021761           -10.7%   25018848   2%  meminfo.AnonPages
>>   64080064   4%     -95.6%    2787565  33%  interrupts.CAL:Function_call_interrupts
>>      13.91   5%     -13.8        0.10  27%  perf-profile.children.cycles-pp.native_queued_spin_lock_slowpath
>> 
> ...snip...
>> test, while in optimized kernel, that is 96.6%.  The TLB flushing IPI
>> (represented as interrupts.CAL:Function_call_interrupts) reduced
>> 95.6%, while cycles for spinlock reduced from 13.9% to 0.1%.  These
>> are performance benefit of THP swapout/swapin too.
>
> Which spinlocks are we spending less time on?

"perf-profile.calltrace.cycles-pp.native_queued_spin_lock_slowpath._raw_spin_lock_irq.mem_cgroup_commit_charge.do_swap_page.__handle_mm_fault": 4.39,
"perf-profile.calltrace.cycles-pp.native_queued_spin_lock_slowpath._raw_spin_lock.free_pcppages_bulk.drain_pages_zone.drain_pages": 1.53,
"perf-profile.calltrace.cycles-pp.native_queued_spin_lock_slowpath._raw_spin_lock.get_page_from_freelist.__alloc_pages_slowpath.__alloc_pages_nodemask": 1.34,
"perf-profile.calltrace.cycles-pp.native_queued_spin_lock_slowpath._raw_spin_lock.swapcache_free_entries.free_swap_slot.do_swap_page": 1.02,
"perf-profile.calltrace.cycles-pp.native_queued_spin_lock_slowpath._raw_spin_lock_irq.shrink_inactive_list.shrink_node_memcg.shrink_node": 0.61,
"perf-profile.calltrace.cycles-pp.native_queued_spin_lock_slowpath._raw_spin_lock_irq.shrink_active_list.shrink_node_memcg.shrink_node": 0.54,

Best Regards,
Huang, Ying