Reduced java/tomcat performance 6-beta3 -> 6-stable ?

[Eirik Øverby]

Hi,

I think I have found the culprit. There must be some sort of  
difference between the machines after all (BIOS revision?), because  
while on one machine the interrupt rate for the bge card stays very  
low (2 to be exact) during maximum load, the other machine goes  
beyond 1000 and keeps rising constantly. This might also explain why  
performance slowly degrades over time on that machine, and response  
times vary wildly, while the "fast" machine responds nicely within  
1-2 seconds no matter the load and testing time.

I will have to investigate this more closely. Is there a way to force  
the NIC to polling mode (I'm assuming that is the difference, an IRQ  
rate of 2 is too low for a heavily loaded server if the NIC is  
interrupt-driven)?

Anything else I could look at?

Also, the interrupt rates for the CPUs stay at 2000 sharp on the fast  
system, but fluctuates somewhat on the other.

/Eirik

On Nov 28, 2005, at 15:54 , Joseph Koshy wrote:

> EØ> *loads* more context switches than on the BETA-3 system.
> EØ> I have not yet tried this during load
>
>  - Which scheduler have you configured (BSD or ULE)?
>  - What do the interrupt statistics show?  Any interrupt
>    storms?  Please check the mailing lists for a prior
>    discussion on interrupt storms on some motherboards.
>  - Could you post the dmesg output from the systems (I
>    presume there aren't any significant differences).
>
> Please CC -stable too.
>
> --
> FreeBSD Volunteer,     http://people.freebsd.org/~jkoshy
>
>