On 01/26/2017 04:47 PM, Bart Van Assche wrote: > On Thu, 2017-01-26 at 16:26 -0700, Jens Axboe wrote: >> What device is stuck? Is it running with an mq scheduler attached, or >> with "none"? >> >> Would also be great to see the output of /sys/block/*/mq/*/tags and >> sched_tags so we can see if they have anything pending. >> >> From a quick look at the below, it looks like a request leak. Bisection >> would most likely be very helpful. > > Hello Jens, > > This happens with and without scheduler attached. The most recent test I ran > was with the deadline scheduler configured as default scheduler for all blk-mq > devices (CONFIG_DEFAULT_SQ_IOSCHED="mq-deadline" and > CONFIG_DEFAULT_MQ_IOSCHED="mq-deadline"). The block devices that hang are > /dev/dm-0 and /dev/dm-1. The tags and sched_tags data is as follows: > > # (cd /sys/class/block && grep -aH '' dm*/mq/*/tags) > dm-0/mq/0/tags:nr_tags=2048, reserved_tags=0, bits_per_word=64 > dm-0/mq/0/tags:nr_free=1795, nr_reserved=0 > dm-0/mq/0/tags:active_queues=0 > dm-1/mq/0/tags:nr_tags=2048, reserved_tags=0, bits_per_word=64 > dm-1/mq/0/tags:nr_free=2047, nr_reserved=0 > dm-1/mq/0/tags:active_queues=0 > # (cd /sys/class/block && grep -aH '' dm*/mq/*/sched_tags) > dm-0/mq/0/sched_tags:nr_tags=256, reserved_tags=0, bits_per_word=64 > dm-0/mq/0/sched_tags:nr_free=0, nr_reserved=0 > dm-0/mq/0/sched_tags:active_queues=0 > dm-1/mq/0/sched_tags:nr_tags=256, reserved_tags=0, bits_per_word=64 > dm-1/mq/0/sched_tags:nr_free=254, nr_reserved=0 > dm-1/mq/0/sched_tags:active_queues=0 Clearly we are missing some requests. How do I setup dm similarly to you? Does it reproduce without Christoph's patchset? -- Jens Axboe -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
