On Tue, 3 Jan 2012 01:21:51 +0000 Jim Jannuzzo <jsqu...@msn.com> wrote:
> There are several processes that can stop the computer > with a long deferred procedure call. I suggest that you > download dpclat.exe from thesyscon.de, and run it. This > will confirm that your problem is indeed with a DPC spike. Is there a way to provoke large DPC latencies? The ideal behaviour of an SDR program would be to issue an error message each time synchronisation is lost, but to recover automatically without user interaction. > Let it run in a little window. Watch for the occurrence > of a red spike (that is, over 1000 us.) If it happens, > you know that is the cause. Big buffers can sometimes > absorb a short spike, but I'm betting something is stalling > your computer more than a little. If you can't immediately > see that a certain program takes some action and causes ' > the DPC spike, the next step is to download LatencyMon > from Resplendence.com. This one will tell you which > process is stalling everything behind it. As the author of an SDR package (Linrad) I would be interseted in knowing how to produce big red spikes. 5 or 10 ms because I want my software to be well behaved also on computers having defective drivers/softwares. I have tried the worst mis-use I can figure out: 1) Set the computer to use one CPU only. 2) Run a program in real time priority and put some computations in the callback routines from system or soundcard to use up 5 ms of CPU time in each callback. That is really silly but I can not see any other consequence than a somewhat larger cpu load. dpclat.exe happily shows 0.1 ms with occasional spikes at 0.9 ms or so. A small utility provoke_dpclat.exe would be very useful. Something that could provoke x ms of dpc latency every y ms. Is there such a program - and if not - is there anyone on this list who knows what it would take to write such a program? 73 Leif / SM5BSZ _______________________________________________ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/
