Hi, > Hi, > > I noticed a performance regression of xfs 6.1.27/6.1.23, > with the compare to xfs 5.15.110. > > It is yet not clear whether it is a problem of xfs or lvm2. > > any guide to troubleshoot it? > > test case: > disk: NVMe PCIe3 SSD *4 > LVM: raid0 default strip size 64K. > fio -name write-bandwidth -rw=write -bs=1024Ki -size=32Gi -runtime=30 > -iodepth 1 -ioengine sync -zero_buffers=1 -direct=0 -end_fsync=1 -numjobs=4 > -directory=/mnt/test > > > 6.1.27/6.1.23 > fio bw=2623MiB/s (2750MB/s) > perf report: > Samples: 330K of event 'cycles', Event count (approx.): 120739812790 > Overhead Command Shared Object Symbol > 31.07% fio [kernel.kallsyms] [k] copy_user_enhanced_fast_string > 5.11% fio [kernel.kallsyms] [k] iomap_set_range_uptodate.part.24 > 3.36% fio [kernel.kallsyms] [k] asm_exc_nmi > 3.29% fio [kernel.kallsyms] [k] native_queued_spin_lock_slowpath > 2.27% fio [kernel.kallsyms] [k] iomap_write_begin > 2.18% fio [kernel.kallsyms] [k] get_page_from_freelist > 2.11% fio [kernel.kallsyms] [k] xas_load > 2.10% fio [kernel.kallsyms] [k] xas_descend > > 5.15.110 > fio bw=6796MiB/s (7126MB/s) > perf report: > Samples: 267K of event 'cycles', Event count (approx.): 186688803871 > Overhead Command Shared Object Symbol > 38.09% fio [kernel.kallsyms] [k] copy_user_enhanced_fast_string > 6.76% fio [kernel.kallsyms] [k] iomap_set_range_uptodate > 4.40% fio [kernel.kallsyms] [k] xas_load > 3.94% fio [kernel.kallsyms] [k] get_page_from_freelist > 3.04% fio [kernel.kallsyms] [k] asm_exc_nmi > 1.97% fio [kernel.kallsyms] [k] native_queued_spin_lock_slowpath > 1.88% fio [kernel.kallsyms] [k] __pagevec_lru_add > 1.53% fio [kernel.kallsyms] [k] iomap_write_begin > 1.53% fio [kernel.kallsyms] [k] __add_to_page_cache_locked > 1.41% fio [kernel.kallsyms] [k] xas_start > more info: 1, 6.2.14 have same performance as 6.1.x 2, 6.1.x fio performance detail: Jobs: 4 (f=4): [W(4)][16.7%][w=10.2GiB/s][w=10.4k IOPS][eta 00m:15s] Jobs: 4 (f=4): [W(4)][25.0%][w=9949MiB/s][w=9949 IOPS][eta 00m:12s] Jobs: 4 (f=4): [W(4)][31.2%][w=9618MiB/s][w=9618 IOPS][eta 00m:11s] Jobs: 4 (f=4): [W(4)][37.5%][w=7970MiB/s][w=7970 IOPS][eta 00m:10s] Jobs: 4 (f=4): [W(4)][41.2%][w=5048MiB/s][w=5047 IOPS][eta 00m:10s] Jobs: 4 (f=4): [W(4)][42.1%][w=2489MiB/s][w=2488 IOPS][eta 00m:11s] Jobs: 4 (f=4): [W(4)][42.9%][w=3227MiB/s][w=3226 IOPS][eta 00m:12s] Jobs: 4 (f=4): [W(4)][45.5%][w=3622MiB/s][w=3622 IOPS][eta 00m:12s] Jobs: 4 (f=4): [W(4)][47.8%][w=3651MiB/s][w=3650 IOPS][eta 00m:12s] Jobs: 4 (f=4): [W(4)][52.2%][w=3435MiB/s][w=3435 IOPS][eta 00m:11s] Jobs: 4 (f=4): [W(4)][52.0%][w=2464MiB/s][w=2463 IOPS][eta 00m:12s] Jobs: 4 (f=4): [W(4)][53.8%][w=2438MiB/s][w=2438 IOPS][eta 00m:12s] Jobs: 4 (f=4): [W(4)][55.6%][w=2435MiB/s][w=2434 IOPS][eta 00m:12s] Jobs: 4 (f=4): [W(4)][57.1%][w=2449MiB/s][w=2448 IOPS][eta 00m:12s] Jobs: 4 (f=4): [W(4)][60.7%][w=2422MiB/s][w=2421 IOPS][eta 00m:11s] Jobs: 4 (f=4): [W(4)][62.1%][w=2457MiB/s][w=2457 IOPS][eta 00m:11s] Jobs: 4 (f=4): [W(4)][63.3%][w=2436MiB/s][w=2436 IOPS][eta 00m:11s] Jobs: 4 (f=4): [W(4)][64.5%][w=2432MiB/s][w=2431 IOPS][eta 00m:11s] Jobs: 4 (f=4): [W(4)][67.7%][w=2440MiB/s][w=2440 IOPS][eta 00m:10s] Jobs: 4 (f=4): [W(4)][71.0%][w=2437MiB/s][w=2437 IOPS][eta 00m:09s] Jobs: 4 (f=4): [W(4)][74.2%][w=2442MiB/s][w=2442 IOPS][eta 00m:08s] Jobs: 4 (f=4): [W(4)][77.4%][w=2425MiB/s][w=2424 IOPS][eta 00m:07s] Jobs: 4 (f=4): [W(4)][80.6%][w=2459MiB/s][w=2459 IOPS][eta 00m:06s] Jobs: 4 (f=4): [W(4)][86.7%][w=2428MiB/s][w=2427 IOPS][eta 00m:04s] Jobs: 4 (f=4): [W(4)][90.0%][w=2441MiB/s][w=2440 IOPS][eta 00m:03s] Jobs: 4 (f=4): [W(4)][93.3%][w=2438MiB/s][w=2437 IOPS][eta 00m:02s] Jobs: 4 (f=4): [W(4)][96.7%][w=2450MiB/s][w=2449 IOPS][eta 00m:01s] Jobs: 4 (f=4): [W(4)][100.0%][w=2430MiB/s][w=2430 IOPS][eta 00m:00s] Jobs: 4 (f=4): [F(4)][100.0%][w=2372MiB/s][w=2372 IOPS][eta 00m:00s] 5.15 fio performance detail: Jobs: 4 (f=4): [W(4)][14.3%][w=8563MiB/s][w=8563 IOPS][eta 00m:18s] Jobs: 4 (f=4): [W(4)][18.2%][w=6376MiB/s][w=6375 IOPS][eta 00m:18s] Jobs: 4 (f=4): [W(4)][20.8%][w=4566MiB/s][w=4565 IOPS][eta 00m:19s] Jobs: 4 (f=4): [W(4)][23.1%][w=3947MiB/s][w=3947 IOPS][eta 00m:20s] Jobs: 4 (f=4): [W(4)][25.9%][w=4601MiB/s][w=4601 IOPS][eta 00m:20s] Jobs: 4 (f=4): [W(4)][28.6%][w=5797MiB/s][w=5796 IOPS][eta 00m:20s] Jobs: 4 (f=4): [W(4)][32.1%][w=6802MiB/s][w=6801 IOPS][eta 00m:19s] Jobs: 4 (f=4): [W(4)][35.7%][w=7411MiB/s][w=7411 IOPS][eta 00m:18s] Jobs: 4 (f=4): [W(4)][40.7%][w=8445MiB/s][w=8444 IOPS][eta 00m:16s] Jobs: 4 (f=4): [W(4)][46.2%][w=7992MiB/s][w=7992 IOPS][eta 00m:14s] Jobs: 4 (f=4): [W(4)][52.0%][w=8118MiB/s][w=8117 IOPS][eta 00m:12s] Jobs: 4 (f=4): [W(4)][56.0%][w=7742MiB/s][w=7741 IOPS][eta 00m:11s] Jobs: 4 (f=4): [W(4)][62.5%][w=7497MiB/s][w=7496 IOPS][eta 00m:09s] Jobs: 4 (f=4): [W(4)][66.7%][w=7248MiB/s][w=7248 IOPS][eta 00m:08s] Jobs: 4 (f=4): [W(4)][70.8%][w=7461MiB/s][w=7460 IOPS][eta 00m:07s] Jobs: 4 (f=4): [W(4)][75.0%][w=7959MiB/s][w=7959 IOPS][eta 00m:06s] Jobs: 4 (f=4): [W(3),F(1)][79.2%][w=6982MiB/s][w=6982 IOPS][eta 00m:05s] Jobs: 1 (f=1): [_(2),W(1),_(1)][87.0%][w=2809MiB/s][w=2808 IOPS][eta 00m:03s] Jobs: 1 (f=1): [_(2),W(1),_(1)][95.5%][w=2669MiB/s][w=2668 IOPS][eta 00m:01s] Jobs: 1 (f=1): [_(2),F(1),_(1)][100.0%][w=2552MiB/s][w=2552 IOPS][eta 00m:00s] 3, 'sysctl -a |grep dirty' of 6.1.x and 5.15.x vm.dirty_background_bytes = 1073741824 vm.dirty_background_ratio = 0 vm.dirty_bytes = 8589934592 vm.dirty_expire_centisecs = 600 vm.dirty_ratio = 0 vm.dirty_writeback_centisecs = 200 vm.dirtytime_expire_seconds = 43200 Best Regards Wang Yugui (wangyugui@xxxxxxxxxxxx) 2023/05/08
