This is the mail archive of the systemtap@sourceware.org mailing list for the systemtap project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Tune reader_thread poll timeout value


Hi, Frederic -


f-turgis wrote:

> [...]
> - with high value such as 5 seconds, low throughput trace is dumped
> only every 5s. So of course, do not use probe timer.s(1) to get
> trace dumped every s on command line, you will have 5 correct infos
> in 1 shot every 5s.
>
> - no impact in performance, when trace throughput is high, ppoll()
> returns before timeout expires. [...]

I'm missing something.  Why does the second item not moot the first?
IOW, if we poll with a 5s timeout, why wouldn't the timer.s(1) reports
wake up the ppoll() to avoid waiting till 5s?


- FChE


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]