From: ext Felipe Contreras <felipe.contreras@xxxxxxxxx> Subject: Re: [PATCH B 3/3] tidspbridge: decreate timeout to a saner value Date: Fri, 20 Mar 2009 01:06:16 +0100 > On Fri, Mar 20, 2009 at 2:00 AM, Guzman Lugo, Fernando <x0095840@xxxxxx> wrote: > > > > > > > > This is a stress test, it creates 4 processes and each process will do 1000 transfers using streams, so the trace is: > > > > STRM_Issue -> WMD_CHNL_AddIOReq -> IO_Schedule > > > > IO_Schedule schedules a call to IO_DPC using task let. > > > > IO_DPC -> IO_DispatchChnl -> InputChnl -> CHNLSM_InterruptDSP2 > > > > Also IO_DispatchChnl -> OutputChnl -> CHNLSM_InterruptDSP2. > > > > > > As we can call a lot CHNLSM_InterruptDSP2 in this test, there is a problem with the timeout. However running other tests, videos and mp3 there no problems. I think we should change to 10ms, only to make sure there is no problem when CHNLSM_InterruptDSP2 is called a lot. > > > > Let me know if you are agreed. Or have some comments about it. > > Well again, the best way to implement the wait for a slot in the > mailbox is with interrupts, not busy-looping. If we busy-loop too much > that would increase the CPU usage, and that would be bad. I think that s/w queuing of messages would be more efficient to allow multiple senders to continue thier work anyway, especially in the case of having these streamings. > > That's why I want to use the 1ms timeout; to find issues that cause > increase in CPU load. > > But for now I think 10ms is the safest, as it's the current value. If > somebody wants to pin-point issues, then the timeout should be > decreased. > > -- > Felipe Contreras -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
