Re: kern/55268: tmpfs is slow

[Andrew Doran <ad%netbsd.org@localhost>]

The following reply was made to PR kern/55268; it has been noted by GNATS.

From: Andrew Doran <ad%netbsd.org@localhost>
To: Andreas Gustafsson <gson%gson.org@localhost>
Cc: gnats-bugs%netbsd.org@localhost
Subject: Re: kern/55268: tmpfs is slow
Date: Sat, 16 May 2020 17:50:15 +0000

 On Sat, May 16, 2020 at 05:23:59PM +0300, Andreas Gustafsson wrote:
 
 > Yes, a little:
 > 
 >   2020.05.14.07.59.03      2167.63 real     10102.86 user     14655.71 sys
 >   2020.05.15.22.35.05      2162.21 real     10105.98 user     14524.89 sys
 
 That's surprising, I guess there's still something up with tmpfs lookup.
 
 Anyway I see the problem, tmpfs doesn't handle PGO_LOCKED.
 
 > With lockstat overhead:
 > 
 >   2020.05.15.22.35.05:     2370.32 real     10290.34 user     16899.28 sys
 > 
 > And the corresponding lockstat output:
 > 
 >   http://www.gson.org/netbsd/bugs/55268/2020.05.15.22.35.05.lockstat.txt
 
 Thanks,
 Andrew