Am 11.02.2013 um 18:08 schrieb Bruce Ashfield: > On Mon, Feb 11, 2013 at 10:54 AM, Ralf Müller <ralf@xxxxxxxx> wrote: >> >> I've got a problem with a box at a customer, where about once a day (overall 20 events in 16 days) a realtime thread blocks for 3 to 4.5 seconds. ... It basically is a loop that wakes up every milli second ... It does this quite well - except for these random multi second sleeps. > > Since you mentioned BIOS, I assume that you are running on a x86 platform. It's x86 - yes. > I noted that you didn't mention if SMIs have been ruled out as a cause of the > latency issues. You've probably already ruled this out, but I figured I'd ask > anyway :) The question is a good one. What I read about SMI when I started this project, said that expected latencies from SMI would be something from some micro- to a maximum of some milliseconds. As my latency constraints are relatively weak - I can perfectly live with 50 microseconds and I would not be happy, but could at least deal with 10 milliseconds every now and then - I did not follow that trail very far. When SMI can really create 3 to 4 seconds blocks I will have to look into that deeper ... anyway - I will have a look at SMI the next days. Thanks a lot for that hint. BTW: Are there any links to SMI events in a multi second range? What in a system is done within such a long time span? Best regards Ralf -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
