Hi Vivek, I have tested with Kata 1.12-apha0, the results seems that are better for the use fio config I am tracking.
The fio config does randrw: fio --direct=1 --gtod_reduce=1 --name=test --filename=random_read_write.fio --bs=4k --iodepth=64 --size=200M --readwrite=randrw --rwmixread=75 - I can see better results with this patch - 9pfs is still better in the case of Kata because of the use of: https://github.com/kata-containers/packaging/blob/stable-1.12/qemu/patches/5.0.x/0001-9p-removing-coroutines-of-9p-to-increase-the-I-O-per.patch Results: ./fio-results-run_virtiofs_tread_pool_0 READ: bw=42.8MiB/s (44.8MB/s), 42.8MiB/s-42.8MiB/s (44.8MB/s-44.8MB/s), io=150MiB (157MB), run=3507-3507msec WRITE: bw=14.3MiB/s (14.9MB/s), 14.3MiB/s-14.3MiB/s (14.9MB/s-14.9MB/s), io=49.0MiB (52.4MB), run=3507-3507msec ./fio-results-run_9pfs READ: bw=55.1MiB/s (57.8MB/s), 55.1MiB/s-55.1MiB/s (57.8MB/s-57.8MB/s), io=150MiB (157MB), run=2722-2722msec WRITE: bw=18.4MiB/s (19.3MB/s), 18.4MiB/s-18.4MiB/s (19.3MB/s-19.3MB/s), io=49.0MiB (52.4MB), run=2722-2722msec ./fio-results-run_virtiofs_tread_pool_1 READ: bw=34.5MiB/s (36.1MB/s), 34.5MiB/s-34.5MiB/s (36.1MB/s-36.1MB/s), io=150MiB (157MB), run=4354-4354msec WRITE: bw=11.5MiB/s (12.0MB/s), 11.5MiB/s-11.5MiB/s (12.0MB/s-12.0MB/s), io=49.0MiB (52.4MB), run=4354-4354msec ./fio-results-run_virtiofs_tread_pool_64 READ: bw=32.3MiB/s (33.8MB/s), 32.3MiB/s-32.3MiB/s (33.8MB/s-33.8MB/s), io=150MiB (157MB), run=4648-4648msec WRITE: bw=10.8MiB/s (11.3MB/s), 10.8MiB/s-10.8MiB/s (11.3MB/s-11.3MB/s), io=49.0MiB (52.4MB), run=4648-4648msec Next: - run https://github.com/rhvgoyal/virtiofs-tests for tread_pool_0, tread_pool_64, and 9pfs - Test https://lore.kernel.org/linux-fsdevel/20201009181512.65496-1-vgo...@redhat.com/ All the testing for kata is based in: https://github.com/jcvenegas/mrunner/blob/master/scripts/bash_workloads/build-qemu-and-run-fio-test.sh I ran this using an azure VM. Cheers, Carlos On 05/11/20 13:53, "Vivek Goyal" <vgo...@redhat.com> wrote: On Thu, Nov 05, 2020 at 02:44:16PM -0500, Vivek Goyal wrote: > Right now we create a thread pool and main thread hands over the request > to thread in thread pool to process. Number of threads in thread pool > can be managed by option --thread-pool-size. > > There is a chance that in case of some workloads, we might get better > performance if we don't handover the request to a different thread > and process in the context of thread receiving the request. > > To implement that, redefine the meaning of --thread-pool-size=0 to > mean that don't use a thread pool. Instead process the request in > the context of thread receiving request from the queue. > > I can't think how --thread-pool-size=0 is useful and hence using > that. If it is already useful somehow, I could look at defining > a new option say "--no-thread-pool". > > I think this patch will be used more as a debug help to do comparison > when it is more effecient to do not hand over the requests to a > thread pool. I ran virtiofs-tests to comapre --thread-pool-size=0 and --thread-pool-size=64. And results seem to be all over the place. In some cases thread pool seems to perform batter and in other cases no-thread-pool seems to perform better. But in general it looks like that except for the case of libaio workload, no-thread-pool is helping. Thanks Vivek NAME WORKLOAD Bandwidth IOPS thread-pool seqread-psync 682.4mb 170.6k no-thread-pool seqread-psync 679.3mb 169.8k thread-pool seqread-psync-multi 2415.9mb 603.9k no-thread-pool seqread-psync-multi 2528.5mb 632.1k thread-pool seqread-mmap 591.7mb 147.9k no-thread-pool seqread-mmap 595.6mb 148.9k thread-pool seqread-mmap-multi 2195.3mb 548.8k no-thread-pool seqread-mmap-multi 2286.1mb 571.5k thread-pool seqread-libaio 329.1mb 82.2k no-thread-pool seqread-libaio 271.5mb 67.8k thread-pool seqread-libaio-multi 1387.1mb 346.7k no-thread-pool seqread-libaio-multi 1508.2mb 377.0k thread-pool randread-psync 59.0mb 14.7k no-thread-pool randread-psync 78.5mb 19.6k thread-pool randread-psync-multi 226.4mb 56.6k no-thread-pool randread-psync-multi 289.2mb 72.3k thread-pool randread-mmap 48.4mb 12.1k no-thread-pool randread-mmap 57.4mb 14.3k thread-pool randread-mmap-multi 183.5mb 45.8k no-thread-pool randread-mmap-multi 240.5mb 60.1k thread-pool randread-libaio 329.4mb 82.3k no-thread-pool randread-libaio 261.8mb 65.4k thread-pool randread-libaio-multi 252.1mb 63.0k no-thread-pool randread-libaio-multi 278.3mb 69.5k thread-pool seqwrite-psync 54.9mb 13.7k no-thread-pool seqwrite-psync 77.8mb 19.4k thread-pool seqwrite-psync-multi 219.9mb 54.9k no-thread-pool seqwrite-psync-multi 314.8mb 78.7k thread-pool seqwrite-mmap 191.7mb 47.9k no-thread-pool seqwrite-mmap 201.4mb 50.3k thread-pool seqwrite-mmap-multi 346.6mb 86.6k no-thread-pool seqwrite-mmap-multi 387.6mb 96.9k thread-pool seqwrite-libaio 306.4mb 76.6k no-thread-pool seqwrite-libaio 248.2mb 62.0k thread-pool seqwrite-libaio-multi 328.5mb 82.1k no-thread-pool seqwrite-libaio-multi 305.6mb 76.4k thread-pool randwrite-psync 55.6mb 13.9k no-thread-pool randwrite-psync 81.2mb 20.3k thread-pool randwrite-psync-multi 227.0mb 56.7k no-thread-pool randwrite-psync-multi 311.6mb 77.8k thread-pool randwrite-mmap 35.3mb 9038 no-thread-pool randwrite-mmap 58.1mb 14.5k thread-pool randwrite-mmap-multi 140.8mb 35.2k no-thread-pool randwrite-mmap-multi 210.5mb 52.6k thread-pool randwrite-libaio 307.1mb 76.7k no-thread-pool randwrite-libaio 279.4mb 69.8k thread-pool randwrite-libaio-multi 361.3mb 90.3k no-thread-pool randwrite-libaio-multi 302.6mb 75.6k thread-pool randrw-psync 34.1mb/11.4mb 8754/2929 no-thread-pool randrw-psync 38.7mb/12.9mb 9919/3321 thread-pool randrw-psync-multi 126.2mb/42.3mb 31.5k/10.5k no-thread-pool randrw-psync-multi 172.2mb/57.7mb 43.0k/14.4k thread-pool randrw-mmap 24.1mb/8270kb 6194/2067 no-thread-pool randrw-mmap 42.0mb/14.0mb 10.5k/3606 thread-pool randrw-mmap-multi 127.9mb/42.8mb 31.9k/10.7k no-thread-pool randrw-mmap-multi 179.4mb/60.0mb 44.8k/15.0k thread-pool randrw-libaio 64.0mb/21.4mb 16.0k/5485 no-thread-pool randrw-libaio 79.6mb/26.6mb 19.9k/6831 thread-pool randrw-libaio-multi 174.2mb/58.3mb 43.5k/14.5k no-thread-pool randrw-libaio-multi 201.6mb/67.5mb 50.4k/16.8k