The main patches are 3/8 and 8/8. 3/8 is to set a new task list and complete its task works prior to the normal task works in old task list. 8/8 is an optimization of batching completion of task works in the new task list if they all have same ctx which is the normal situation, the benefit is we now batch them regardless uring_lock. Tested this patchset by manually replace __io_queue_sqe() by io_req_task_complete() to construct 'heavy' task works. Then test with fio: ioengine=io_uring thread=1 bs=4k direct=1 rw=randread time_based=1 runtime=600 randrepeat=0 group_reporting=1 filename=/dev/nvme0n1 Tried various iodepth. The peak IOPS for this patch is 314K, while the old one is 249K. For avg latency, difference shows when iodepth grow: depth and avg latency(usec): depth new old 1 22.80 23.77 2 23.48 24.54 4 24.26 25.57 8 29.21 32.89 16 53.61 63.50 32 106.29 131.34 64 217.21 256.33 128 421.59 513.87 256 815.15 1050.99 without this patchset iodepth=1 clat percentiles (usec): | 1.00th=[ 7], 5.00th=[ 7], 10.00th=[ 8], 20.00th=[ 8], | 30.00th=[ 8], 40.00th=[ 8], 50.00th=[ 8], 60.00th=[ 8], | 70.00th=[ 8], 80.00th=[ 8], 90.00th=[ 82], 95.00th=[ 97], | 99.00th=[ 99], 99.50th=[ 99], 99.90th=[ 100], 99.95th=[ 101], | 99.99th=[ 126] iodepth=2 clat percentiles (usec): | 1.00th=[ 7], 5.00th=[ 7], 10.00th=[ 7], 20.00th=[ 8], | 30.00th=[ 8], 40.00th=[ 8], 50.00th=[ 8], 60.00th=[ 9], | 70.00th=[ 10], 80.00th=[ 10], 90.00th=[ 83], 95.00th=[ 97], | 99.00th=[ 100], 99.50th=[ 102], 99.90th=[ 126], 99.95th=[ 145], | 99.99th=[ 971] iodepth=4 clat percentiles (usec): | 1.00th=[ 7], 5.00th=[ 7], 10.00th=[ 8], 20.00th=[ 8], | 30.00th=[ 8], 40.00th=[ 9], 50.00th=[ 9], 60.00th=[ 10], | 70.00th=[ 11], 80.00th=[ 13], 90.00th=[ 86], 95.00th=[ 98], | 99.00th=[ 105], 99.50th=[ 115], 99.90th=[ 139], 99.95th=[ 149], | 99.99th=[ 169] iodepth=8 clat percentiles (usec): | 1.00th=[ 7], 5.00th=[ 8], 10.00th=[ 9], 20.00th=[ 12], | 30.00th=[ 13], 40.00th=[ 16], 50.00th=[ 18], 60.00th=[ 20], | 70.00th=[ 22], 80.00th=[ 27], 90.00th=[ 95], 95.00th=[ 105], | 99.00th=[ 121], 99.50th=[ 131], 99.90th=[ 157], 99.95th=[ 167], | 99.99th=[ 206] iodepth=16 clat percentiles (usec): | 1.00th=[ 25], 5.00th=[ 33], 10.00th=[ 37], 20.00th=[ 41], | 30.00th=[ 44], 40.00th=[ 46], 50.00th=[ 49], 60.00th=[ 51], | 70.00th=[ 55], 80.00th=[ 63], 90.00th=[ 125], 95.00th=[ 137], | 99.00th=[ 155], 99.50th=[ 165], 99.90th=[ 198], 99.95th=[ 235], | 99.99th=[ 1844] iodepth=32 clat percentiles (usec): | 1.00th=[ 92], 5.00th=[ 98], 10.00th=[ 102], 20.00th=[ 106], | 30.00th=[ 110], 40.00th=[ 112], 50.00th=[ 116], 60.00th=[ 120], | 70.00th=[ 128], 80.00th=[ 141], 90.00th=[ 192], 95.00th=[ 204], | 99.00th=[ 227], 99.50th=[ 235], 99.90th=[ 260], 99.95th=[ 273], | 99.99th=[ 322] iodepth=64 clat percentiles (usec): | 1.00th=[ 221], 5.00th=[ 227], 10.00th=[ 231], 20.00th=[ 233], | 30.00th=[ 237], 40.00th=[ 239], 50.00th=[ 241], 60.00th=[ 243], | 70.00th=[ 247], 80.00th=[ 253], 90.00th=[ 318], 95.00th=[ 330], | 99.00th=[ 351], 99.50th=[ 359], 99.90th=[ 388], 99.95th=[ 400], | 99.99th=[ 529] iodepth=128 clat percentiles (usec): | 1.00th=[ 465], 5.00th=[ 478], 10.00th=[ 482], 20.00th=[ 486], | 30.00th=[ 490], 40.00th=[ 490], 50.00th=[ 494], 60.00th=[ 498], | 70.00th=[ 506], 80.00th=[ 553], 90.00th=[ 578], 95.00th=[ 586], | 99.00th=[ 635], 99.50th=[ 652], 99.90th=[ 676], 99.95th=[ 717], | 99.99th=[ 2278] iodepth=256 clat percentiles (usec): | 1.00th=[ 979], 5.00th=[ 988], 10.00th=[ 996], 20.00th=[ 1012], | 30.00th=[ 1020], 40.00th=[ 1037], 50.00th=[ 1037], 60.00th=[ 1045], | 70.00th=[ 1057], 80.00th=[ 1090], 90.00th=[ 1123], 95.00th=[ 1139], | 99.00th=[ 1205], 99.50th=[ 1237], 99.90th=[ 1254], 99.95th=[ 1270], | 99.99th=[ 1385] with this patchset iodepth=1 clat percentiles (usec): | 1.00th=[ 7], 5.00th=[ 7], 10.00th=[ 7], 20.00th=[ 7], | 30.00th=[ 7], 40.00th=[ 7], 50.00th=[ 8], 60.00th=[ 8], | 70.00th=[ 8], 80.00th=[ 8], 90.00th=[ 82], 95.00th=[ 97], | 99.00th=[ 99], 99.50th=[ 99], 99.90th=[ 100], 99.95th=[ 101], | 99.99th=[ 125] iodepth=2 clat percentiles (usec): | 1.00th=[ 6], 5.00th=[ 7], 10.00th=[ 7], 20.00th=[ 7], | 30.00th=[ 7], 40.00th=[ 7], 50.00th=[ 8], 60.00th=[ 8], | 70.00th=[ 9], 80.00th=[ 11], 90.00th=[ 83], 95.00th=[ 97], | 99.00th=[ 100], 99.50th=[ 102], 99.90th=[ 127], 99.95th=[ 141], | 99.99th=[ 668] iodepth=4 clat percentiles (usec): | 1.00th=[ 6], 5.00th=[ 6], 10.00th=[ 7], 20.00th=[ 7], | 30.00th=[ 7], 40.00th=[ 8], 50.00th=[ 8], 60.00th=[ 9], | 70.00th=[ 10], 80.00th=[ 12], 90.00th=[ 85], 95.00th=[ 97], | 99.00th=[ 104], 99.50th=[ 115], 99.90th=[ 141], 99.95th=[ 149], | 99.99th=[ 194] iodepth=8 clat percentiles (usec): | 1.00th=[ 6], 5.00th=[ 7], 10.00th=[ 7], 20.00th=[ 9], | 30.00th=[ 11], 40.00th=[ 12], 50.00th=[ 14], 60.00th=[ 15], | 70.00th=[ 18], 80.00th=[ 22], 90.00th=[ 93], 95.00th=[ 103], | 99.00th=[ 120], 99.50th=[ 130], 99.90th=[ 157], 99.95th=[ 167], | 99.99th=[ 208] iodepth=16 clat percentiles (usec): | 1.00th=[ 16], 5.00th=[ 24], 10.00th=[ 28], 20.00th=[ 32], | 30.00th=[ 34], 40.00th=[ 37], 50.00th=[ 39], 60.00th=[ 41], | 70.00th=[ 44], 80.00th=[ 51], 90.00th=[ 117], 95.00th=[ 128], | 99.00th=[ 147], 99.50th=[ 159], 99.90th=[ 194], 99.95th=[ 235], | 99.99th=[ 1909] iodepth=32 clat percentiles (usec): | 1.00th=[ 72], 5.00th=[ 78], 10.00th=[ 81], 20.00th=[ 84], | 30.00th=[ 86], 40.00th=[ 88], 50.00th=[ 90], 60.00th=[ 93], | 70.00th=[ 96], 80.00th=[ 114], 90.00th=[ 169], 95.00th=[ 182], | 99.00th=[ 202], 99.50th=[ 212], 99.90th=[ 239], 99.95th=[ 253], | 99.99th=[ 302] iodepth=64 clat percentiles (usec): | 1.00th=[ 178], 5.00th=[ 184], 10.00th=[ 186], 20.00th=[ 192], | 30.00th=[ 196], 40.00th=[ 200], 50.00th=[ 204], 60.00th=[ 206], | 70.00th=[ 210], 80.00th=[ 221], 90.00th=[ 281], 95.00th=[ 293], | 99.00th=[ 318], 99.50th=[ 330], 99.90th=[ 355], 99.95th=[ 367], | 99.99th=[ 437] iodepth=128 clat percentiles (usec): | 1.00th=[ 379], 5.00th=[ 388], 10.00th=[ 392], 20.00th=[ 396], | 30.00th=[ 396], 40.00th=[ 400], 50.00th=[ 404], 60.00th=[ 408], | 70.00th=[ 424], 80.00th=[ 437], 90.00th=[ 482], 95.00th=[ 498], | 99.00th=[ 529], 99.50th=[ 537], 99.90th=[ 570], 99.95th=[ 635], | 99.99th=[ 2311] iodepth=256 clat percentiles (usec): | 1.00th=[ 783], 5.00th=[ 783], 10.00th=[ 791], 20.00th=[ 791], | 30.00th=[ 791], 40.00th=[ 799], 50.00th=[ 799], 60.00th=[ 799], | 70.00th=[ 807], 80.00th=[ 816], 90.00th=[ 881], 95.00th=[ 889], | 99.00th=[ 914], 99.50th=[ 930], 99.90th=[ 979], 99.95th=[ 996], | 99.99th=[ 1237] Hao Xu (8): io-wq: code clean for io_wq_add_work_after() io-wq: add helper to merge two wq_lists io_uring: add a limited tw list for irq completion work io_uring: add helper for task work execution code io_uring: split io_req_complete_post() and add a helper io_uring: move up io_put_kbuf() and io_put_rw_kbuf() io_uring: add tw_ctx for io_uring_task io_uring: batch completion in prior_task_list fs/io-wq.h | 27 ++++++-- fs/io_uring.c | 171 ++++++++++++++++++++++++++++++++++---------------- 2 files changed, 139 insertions(+), 59 deletions(-) -- 2.24.4
