On Tue, May 26, 2009 at 9:48 PM, Grant Likely <grant.likely@xxxxxxxxxxxx> wrote: > First, udelay just burns time, and if the delay is too large, then the > it is wasting time that could be used for something else. That being > said, it needs to be balanced with the context switch overhead. If > the udelay() is less than double the context switch time, then the > overhead is greater than the time spent spinning. BTW, lmbench lat_ctx test case tells me that context switch latency is measured somewhere around 30 to 60 us for user space processes sleeping on a file descriptor. That will be lower for kernel threads since there is no syscall overhead to account for. g. -- Grant Likely, B.Sc., P.Eng. Secret Lab Technologies Ltd. _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
