Re: [PATCH 1/2] pidmap(2)

[Randy Dunlap]

On 09/05/17 15:53, Andrew Morton wrote:
> On Tue, 5 Sep 2017 22:05:00 +0300 Alexey Dobriyan <adobriyan@xxxxxxxxx> wrote:
> 
>> Implement system call for bulk retrieveing of pids in binary form.
>>
>> Using /proc is slower than necessary: 3 syscalls + another 3 for each thread +
>> converting with atoi().
>>
>> /proc may be not mounted especially in containers. Natural extension of
>> hidepid=2 efforts is to not mount /proc at all.
>>
>> It could be used by programs like ps, top or CRIU. Speed increase will
>> become more drastic once combined with bulk retrieval of process statistics.
> 
> The patches are performance optimizations, but their changelogs contain
> no performance measurements!
> 
> Demonstration of some compelling real-world performance benefits would
> help things along a lot.
> 

also, I expect that the tiny kernel people will want kconfig options for
these syscalls.

-- 
~Randy