Bug 232940

Summary: Investigate poor ncsd performance reported in bug 230491
Product: Base System Reporter: Conrad Meyer <cem>
Component: binAssignee: 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.