On Fri, Jun 16, 2023 at 8:27 PM Yu Kuai <yukuai1@xxxxxxxxxxxxxxx> wrote: > > Hi, > > 在 2023/06/16 19:51, Ali Gholami Rudi 写道: > > > > Thanks for testing! > > > Perf's output: > > > > + 93.79% 0.09% fio [kernel.kallsyms] [k] entry_SYSCALL_64_after_hwframe > > + 92.89% 0.05% fio [kernel.kallsyms] [k] do_syscall_64 > > + 86.59% 0.07% fio [kernel.kallsyms] [k] __x64_sys_io_submit > > - 85.61% 0.10% fio [kernel.kallsyms] [k] io_submit_one > > - 85.51% io_submit_one > > - 47.98% aio_read > > - 46.18% blkdev_read_iter > > - 44.90% __blkdev_direct_IO_async > > - 41.68% submit_bio_noacct_nocheck > > - 41.50% __submit_bio > > - 18.76% md_handle_request > > - 18.71% raid10_make_request > > - 18.54% raid10_read_request > > 16.54% read_balance > > There is not any spin_lock in fast path anymore. Now, looks like > main cost is raid10 io path now(read_balance looks worth > investigation, 16.54% is too much), and for a real device with ms > io latency, I think latency in io path may not matter. Hi Kuai Cool. And I noticed you mentioned 'fast path' in many places. What's the meaning of 'fast path'? Does it mean the path that i/os are submitting? Regards Xiao
