Török Edwin wrote: > On 2008-07-18 13:31, Martin Peschke wrote: >> recent changes: >> - added man page >> - beautified human-readable output >> - fixed an x86 compile error caused by incomplete endianess handling >> - fixed some x86 __u64 vs. unsigned long compiler warnings >> - fixed checking of a command line argument >> >> >> blkiomon periodicaly generates per devive request size and request latency >> statistics from blktrace data. It provides histograms as well as data that >> > > Does it also measure latency caused by the request queues being full? > (which happens around here): > blk-core.c:get_request: > /* > * The queue is full and the allocating > * process is not a "batcher", and not > * exempted by the IO scheduler > */ > goto out; > > That would be very useful to trace some high latencies I am seeing, see > discussion here: > http://lkml.org/lkml/2008/7/12/104 > > Best regards, > --Edwin Hi Edwin - It would probably be pretty hard to do so - Martin is mostly interested in issue & complete information. The stuff you needs comes from sleep requests. The btt tool is static, but does output some data concerning the amount of time spent "sleeping" - waiting for a request to be made available. (But only for the whole duration of the run, you're looking for an instantaneous output.) I've also looked at seekwatcher - but it too just looks at the issue & complete stuff, but I will see if there is some way of handling sleep request stuff "live". Alan -- To unsubscribe from this list: send the line "unsubscribe linux-btrace" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
