ULE status

[Ion-Mihai Tetcu]

On Tue, 8 Feb 2005 08:39:15 -0800
Kris Kennaway <kris at obsecurity.org> wrote:

> On Tue, Feb 08, 2005 at 03:58:22PM +0200, Ion-Mihai Tetcu wrote:
> > On Tue, 8 Feb 2005 14:45:17 +0200 (EET)
> > "Viktor Ivanov" <v0rbiz at icon.bg> wrote:
> > 

 [ ... ]

> > > On the other hand, using SCHED_ULE improves sound quality and general
> > > system 'response' concerning GUI... don't know 'bout performance.
> > 
> > By any chance does it help with copying from ata disks on different
> > controllers ? For me on large files this brings up "swap_pager:
> > indefinite wait buffer" with 4BSD.
> 
> That doesn't sound like a scheduler problem, rather a hardware or ata
> driver problem.  Did you try sos' new driver yet?

Well, I'm running my desktop with an ULE kernel now, snippets bellow:
options         SCHED_ULE               # ULE scheduler
options         ADAPTIVE_GIANT          # Giant mutex is adaptive.
options         HZ=1200
options         INVARIANTS              # Enable calls of extra sanity checking
options         INVARIANT_SUPPORT       # Extra sanity checks of internal structures,
#                                        required by INVARIANTS
options         WITNESS                 # Enable checks to detect deadlocks and cycles
options         WITNESS_SKIPSPIN        # Don't run witness on spinlocks for speed

and
 # sysctl debug.witness
debug.witness.skipspin: 1
debug.witness.trace: 1
debug.witness.kdb: 0
debug.witness.watch: 0


And while I don't see may improvements in general operation, at least
this problem is gone. I still get a few seconds pauses in sound and
switching between app in X is sluggish while copying large files, but at
least I don't get swap pager complains and I'd say there's a 3x
responsiveness improvement.


I didn't test ata patches yet, just to take one step at the time.

-- 
IOnut
Unregistered ;) FreeBSD "user"