Exactly!  If the driver is doing it's job, then the
problem's likely in the handler. It's that loop over
all the fd's that's needed.

stephane eranian wrote:
> Rob,
> 
> On Fri, Apr 18, 2008 at 5:09 PM, Rob Fowler <[EMAIL PROTECTED]> wrote:
>> I've been spending way too much time being a manager lately
>>  to actually dig around in the Perfmon code,
>>  but my gut feeling on this issue continues to be that the
>>  problem is one of two things:
>>
>>  Second, the PAPI workaround of using SIGRTMIN rather than SIGIO leads me
>>  to suspect that a second or third trap occurs while the first is being
>>  handled and that going to queued signals ensures that multiple events are
>>  delivered in separate signals.  This is a consequence of usgin a
>>  "1-signal = 1-event" assumption.
>>
> This interpretation is not imposed by the interface. This is an
> assumption made by
> the signal handler.
> 
> Perfmon does send one signal per 64bit overflow but it also enqueues
> one message per
> context. If signal get aggregated, then sure you will "miss" some
> overflows. However
> the information is not completely lost as the messages are still
> enqueue. In the handler
> you could simply poll all perfmon file descriptors using a
> non-blocking read on each fd.
> That way you would be sure you've swept all possible source of overflows.

-- 
Robert J. Fowler
Chief Domain Scientist, HPC
Renaissance Computing Institute
The University of North Carolina at Chapel Hill
100 Europa Dr, Suite 540
Chapel Hill, NC 27517
V: 919.445.9670
F: 919 445.9669
[EMAIL PROTECTED]

-------------------------------------------------------------------------
This SF.net email is sponsored by the 2008 JavaOne(SM) Conference 
Don't miss this year's exciting event. There's still time to save $100. 
Use priority code J8TL2D2. 
http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone
_______________________________________________
perfmon2-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/perfmon2-devel

Reply via email to