[lkml]   [2021]   [Mar]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH v5] do_wait: make PIDTYPE_PID case O(1) instead of O(n)
On Fri, 12 Mar 2021 11:38:55 -0600 Jim Newsome <> wrote:

> do_wait is an internal function used to implement waitpid, waitid,
> wait4, etc. To handle the general case, it does an O(n) linear scan of
> the thread group's children and tracees.
> This patch adds a special-case when waiting on a pid to skip these scans
> and instead do an O(1) lookup. This improves performance when waiting on
> a pid from a thread group with many children and/or tracees.

Could we please see some performance testing results to permit us to
evaluate the value of this change?


 \ /
  Last update: 2021-03-12 19:23    [W:0.088 / U:0.308 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site