Messages in this thread | | | Subject | Re: AW: Slow I/O on USB media after commit f664a3cc17b7d0a2bc3b3ab96181e1029b0ec0e6 | From | Andrea Vai <> | Date | Mon, 23 Dec 2019 17:29:27 +0100 |
| |
Il giorno lun, 23/12/2019 alle 11.26 -0500, Theodore Y. Ts'o ha scritto: > On Mon, Dec 23, 2019 at 09:08:28PM +0800, Ming Lei wrote: > > > > From the above trace: > > > > b'blk_mq_sched_request_inserted' > > b'blk_mq_sched_request_inserted' > > b'dd_insert_requests' > > b'blk_mq_sched_insert_requests' > > b'blk_mq_flush_plug_list' > > b'blk_flush_plug_list' > > b'io_schedule_prepare' > > b'io_schedule' > > b'rq_qos_wait' > > b'wbt_wait' > > b'__rq_qos_throttle' > > b'blk_mq_make_request' > > b'generic_make_request' > > b'submit_bio' > > b'ext4_io_submit' > > b'ext4_writepages' > > b'do_writepages' > > b'__filemap_fdatawrite_range' > > b'ext4_release_file' > > b'__fput' > > b'task_work_run' > > b'exit_to_usermode_loop' > > b'do_syscall_64' > > b'entry_SYSCALL_64_after_hwframe' > > b'cp' [19863] > > 4400 > > > > So this write is clearly from 'cp' process, and it should be one > > ext4 fs issue. > > We need a system call trace of the cp process, to understand what > system call is resulting in fput, (eg., I assume it's close(2) but > let's be sure), and often it's calling that system call. > > What cp process is it? Is it from shellutils? Is it from busybox? > > - Ted
I run the cp command from a bash script, or from a bash shell. I don't know if this answer your question, otherwise feel free to tell me a way to find the answer to give you.
Thanks, Andrea
| |