Bug 232940

Summary:	Investigate poor ncsd performance reported in bug 230491
Product:	Base System	Reporter:	Conrad Meyer <cem>
Component:	bin	Assignee:	freebsd-bugs (Nobody) <bugs>
Status:	New ---
Severity:	Affects Only Me	CC:	gad, tom
Priority:	---	Keywords:	performance
Version:	CURRENT
Hardware:	Any
OS:	Any
Bug Depends on:	230491
Bug Blocks:

Description Conrad Meyer freebsd_committer

2018-11-03 16:37:15 UTC

See comments #2, 5, 6, and 14 on bug 230491.

> The built-in caching doesn't seem useful for this case.  Enabling it results in a test run creating this unfortunate entry in top:
>
> 63957 root             9  52    0 24000K  4696K uwait  19   9:15 268.91% nscd
>
> and actually *slows down* stat(1) in my tests - /usr/src goes from 22 seconds to almost 90, and my CVS repository scan goes from 55 seconds to 2 minutes.


> Reducing thread count improves performance with nscd, but at "threads 1" it's still 52s vs 22s uncached.