signifanctly slowdown of FreeBSD 8.0-CURRENT/amd64

[Randall Stewart]

One thing I have noticed for a while.. and have not
been able to track down..

If one runs

/usr/src/tools/tools/syscall_timing/syscall_timing

On a 7.2 kernel and compare it on the same machine to an 8.0 kernel
you will see almost a 3x slow down in 8.

Yes I have 8.0 without witness and all the debug. The thing
that is most interesting is I even ran 8 on a 7.2 user space...
same result.

My AMD 64 1.6Gig  8 core machines (in SMP) are showing

250ns or so for getuid 1000 times on 7.2
and
880ns or so for getuid 1000 times on 8.0

I started tracking this in 7.1..

When I get some more time next week I will do some more digging.. not  
sure
its related to this issue though

R

On Jun 14, 2009, at 2:14 PM, Pierre Guinoiseau wrote:

> Hi again,
>
> I don't know if it can be of better help or not, but I made 2 other
> dumps, before and after the slowdown, and without X running and  
> all... I
> recompiled some packages several times to make the slowdown appear.
>
> The dumps are here : http://foo.poildetroll.net/freebsd/ktr/
>
> Thanks again for your help!
>
> Pierre Guinoiseau
>
>
> Attilio Rao wrote:
>> 2009/6/7 Pierre Guinoiseau <geekounet at poildetroll.net>:
>>> Ok, here is a ktr output. This time, the slowdown appeared while
>>> recompiling thunderbird. I have 2 core at 2.2Ghz (and powerd  
>>> running, I
>>> don't know if it matters).
>>>
>>> BTW, what is the use of py-tkinter ? If it was in order to cause the
>>> bug, it failed, it needed a higher load. :)
>>
>> Ah sorry, I was supposed to let you run schedgraph but I'm going to  
>> do
>> that, so you actually didn't need it
>> I will let you know if something cames up.
>> If others can report the same it will be great.
>>
>> Thanks,
>> Attilio
>> _______________________________________________
>> freebsd-current at freebsd.org mailing list
>> http://lists.freebsd.org/mailman/listinfo/freebsd-current
>> To unsubscribe, send any mail to "freebsd-current-unsubscribe at freebsd.org 
>> "
>

------------------------------
Randall Stewart
803-317-4952 (cell)
803-345-0391(direct)