Re: [PATCH v2 0/2] Replace PID bitmap allocation with IDR API

Gargi Sharma
2017-09-28T20:06:14Z

On Thu, Sep 28, 2017 at 3:46 PM, Rik van Riel <riel@surriel.com> wrote:
> On Fri, 2017-09-29 at 01:09 +0530, Gargi Sharma wrote:
>
>> 1000 processes that just sleep and sit around without doing
>> anything(100 second sleep and then exit).
>>
>> pstree with 10,000 processes
>> real 0m0.859s
>> user 0m0.536s
>> sys 0m0.172s
>>
>> ps with 10,000 processes
>> real 0m0.918s
>> user 0m0.100s
>> sys 0m0.172s
>>
>> Stats for calling readdir on /proc with 10,000 processes
>> real 0m0.092s
>> user 0m0.000s
>> sys 0m0.020s
>
> Is that with or without your patches?
>
> How does it compare to a kernel with(out) your patches?
Ah thanks for pointing this out. Those were without the patches.
Here are the stats for easier comparison.

With Patches Without patches
pstree
real 0m0.542s real 0m0.859s
user 0m0.335s user 0m0.536s
sys 0m0.150s sys 0m0.172s

ps
real 0m0.722s real 0m0.918s
user 0m0.064s user 0m0.100s
sys 0m0.162s sys 0m0.172s

readdir
real 0m0.080s real 0m0.092s
user 0m0.000s user 0m0.000s
sys 0m0.021s sys 0m0.020s

Thanks!
Gargi
>
> --
> All Rights Reversed.

On Fri, Sep 29, 2017 at 1:16 AM, Rik van Riel <riel@surriel.com> wrote:
> On Fri, 2017-09-29 at 01:09 +0530, Gargi Sharma wrote:
>
>> 1000 processes that just sleep and sit around without doing
>> anything(100 second sleep and then exit).
>>
>> pstree with 10,000 processes
>> real 0m0.859s
>> user 0m0.536s
>> sys 0m0.172s
>>
>> ps with 10,000 processes
>> real 0m0.918s
>> user 0m0.100s
>> sys 0m0.172s
>>
>> Stats for calling readdir on /proc with 10,000 processes
>> real 0m0.092s
>> user 0m0.000s
>> sys 0m0.020s
>
> Is that with or without your patches?
>
> How does it compare to a kernel with(out) your patches?
>
> --
> All Rights Reversed.