From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <53F79442.6010500@kernel.dk> Date: Fri, 22 Aug 2014 14:04:34 -0500 From: Jens Axboe MIME-Version: 1.0 Subject: Re: fio main thread got stuck over the weekend References: <20140811154423.GE7486@beardog.cce.hp.com> <20140811160418.GG7486@beardog.cce.hp.com> In-Reply-To: <20140811160418.GG7486@beardog.cce.hp.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit To: scameron@beardog.cce.hp.com, fio@vger.kernel.org List-ID: On 2014-08-11 11:04, scameron@beardog.cce.hp.com wrote: > On Mon, Aug 11, 2014 at 10:44:23AM -0500, scameron@beardog.cce.hp.com wrote: >> >> Hi, >> >> I was running an fio job over the weekend and the main thread >> seems to have hung. This in on RHEL6u5 with kernel >> 2.6.32-431.20.3.el6.x86_64 but with a highly modified hpsa >> driver, just in case it matters. >> >> [root@msablackburn saperf]# uname -a >> Linux msablackburn.americas.hpqcorp.net 2.6.32-431.20.3.el6.x86_64 #1 SMP Fri Jun 6 18:30:54 EDT 2014 x86_64 x86_64 x86_64 GNU/Linux >> [root@msablackburn saperf]# /usr/local/bin/fio --version >> fio-2.1.11-3-g789d >> >> The jobfile looks like this (note the runtime=216000, that's 60 hours) >> It seems to have hung with about 25 hours remaining.) >> >> [root@msablackburn saperf]# cat 2drive_sdr.fio >> [global] >> direct=1 >> ioengine=libaio >> norandommap >> randrepeat=0 >> bs=4096 >> iodepth=1011 >> #iodepth=96 >> #numjobs=1 >> numjobs=12 >> #numjobs=24 >> # number_ios=1 >> runtime=216000 >> #runtime=54000 >> time_based=1 >> group_reporting >> thread >> gtod_reduce=1 >> #iodepth_batch=4 >> #iodepth_batch_complete=4 >> cpus_allowed=0-5 >> cpus_allowed_policy=split >> rw=randread >> >> [4_KiB_RR_drive_r] >> filename=/dev/sdr >> >> [4_KiB_RR_drive_s] >> filename=/dev/sds >> >> >> Here is all the output so far: >> >> ---------------8<------------8<-------------8<----------------- >> [root@msablackburn saperf]# fio 2drive_sdr.fio >> 4_KiB_RR_drive_r: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=1011 >> ... >> 4_KiB_RR_drive_s: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=1011 >> ... >> fio-2.1.11-3-g789d >> Starting 24 threads >> ^Cbs: 24 (f=24): [r(24)] [1.2% done] [1113MB/0KB/0KB /s] [285K/0/0 iops] [eta 14h:48m:47s] >> fio: terminating on signal 2 >> >> 4_KiB_RR_drive_r: (groupid=0, jobs=24): err= 0: pid=7696: Fri Aug 8 16:49:19 2014 >> read : io=881568MB, bw=1309.1MB/s, iops=335341, runt=672989msec >> cpu : usr=1.75%, sys=23.15%, ctx=1266117, majf=9, minf=835 >> IO depths : 1=0.1%, 2=0.1%, 4=0.1%, 8=0.1%, 16=0.1%, 32=0.1%, >=64=100.0% >> submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% >> complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.1% >> issued : total=r=225681428/w=0/d=0, short=r=0/w=0/d=0 >> latency : target=0, window=0, percentile=100.00%, depth=1011 >> >> Run status group 0 (all jobs): >> READ: io=881568MB, aggrb=1309.1MB/s, minb=1309.1MB/s, maxb=1309.1MB/s, mint=672989msec, maxt=672989msec >> >> Disk stats (read/write): >> sdr: ios=112299535/0, merge=0/0, ticks=13349007/0, in_queue=13054755, util=98.57% >> sds: ios=113359581/0, merge=0/0, ticks=13710834/0, in_queue=13414931, util=98.71% >> [root@msablackburn saperf]# vi !$ >> vi 2drive_sdr.fio >> [root@msablackburn saperf]# fio 2drive_sdr.fio >> 4_KiB_RR_drive_r: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=1011 >> ... >> 4_KiB_RR_drive_s: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=1011 >> ... >> fio-2.1.11-3-g789d >> Starting 24 threads >> Jobs: 24 (f=24): [r(24)] [57.1% done] [1408MB/0KB/0KB /s] [361K/0/0 iops] [eta 01d:01h:43m:07s] >> ---------------8<------------8<-------------8<----------------- >> >> And there it sits, the eta does not update. >> >> >> I tried connecting to the process with gdb, and doing "info threads" and "bt": >> >> PID of main thread is 8530: >> >> root 8530 598 1.0 2159116 170812 pts/0 Sl+ Aug08 23570:56 fio 2drive_sdr.fio >> >> ... >> (gdb) info threads >> 26 Thread 0x7f65da431700 (LWP 8531) 0x0000003aa4cacced in nanosleep () from /lib64/libc.so.6 >> 25 Thread 0x7f65d9a30700 (LWP 8532) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 24 Thread 0x7f65d902f700 (LWP 8533) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 23 Thread 0x7f65d862e700 (LWP 8534) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 22 Thread 0x7f65d7c2d700 (LWP 8535) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 21 Thread 0x7f65d722c700 (LWP 8536) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 20 Thread 0x7f65d682b700 (LWP 8537) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 19 Thread 0x7f65d5e2a700 (LWP 8538) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 18 Thread 0x7f65d5429700 (LWP 8539) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 17 Thread 0x7f65d4a28700 (LWP 8540) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 16 Thread 0x7f65d4027700 (LWP 8541) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 15 Thread 0x7f65d3626700 (LWP 8542) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 14 Thread 0x7f65d2c25700 (LWP 8543) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 13 Thread 0x7f65d2222700 (LWP 8544) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 12 Thread 0x7f65d1820700 (LWP 8545) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 11 Thread 0x7f65d0e1e700 (LWP 8546) td_io_queue (td=0x7f65da496410, io_u=0x7f656804d010) at ioengines.c:344 >> 10 Thread 0x7f65d041c700 (LWP 8547) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 9 Thread 0x7f65cfa1a700 (LWP 8548) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 8 Thread 0x7f65cf018700 (LWP 8549) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 7 Thread 0x7f65ce616700 (LWP 8550) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 6 Thread 0x7f65cdc14700 (LWP 8551) fio_libaio_event (td=0x7f65da4b06a8, event=) at engines/libaio.c:65 >> 5 Thread 0x7f65cd212700 (LWP 8552) __get_next_offset (td=0x7f65da4b5a60) at io_u.c:389 >> 4 Thread 0x7f65cc810700 (LWP 8553) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> 3 Thread 0x7f65cbe0e700 (LWP 8554) td_io_u_unlock (td=0x7f65da4c01d0, min_evts=, bytes=0x7f65cbe0dd10) at fio.h:619 >> 2 Thread 0x7f65cb40c700 (LWP 8555) 0x0000003c69800667 in io_submit () from /lib64/libaio.so.1 >> * 1 Thread 0x7f65e34c6720 (LWP 8530) 0x0000003aa4cacced in nanosleep () from /lib64/libc.so.6 >> (gdb) bt >> #0 0x0000003aa4cacced in nanosleep () from /lib64/libc.so.6 >> #1 0x0000003aa4ce1e44 in usleep () from /lib64/libc.so.6 >> #2 0x000000000044afe4 in do_usleep () at backend.c:1727 >> #3 run_threads () at backend.c:1965 >> #4 0x000000000044b84d in fio_backend () at backend.c:2068 >> #5 0x0000003aa4c1ed1d in __libc_start_main () from /lib64/libc.so.6 >> #6 0x0000000000409c39 in _start () >> (gdb) detach >> Detaching from program: /usr/local/bin/fio, process 8530 >> (gdb) quit >> [root@msablackburn saperf]# >> >> I am guessing the 8530 thread is the one that prints out the eta updates? >> Well, maybe not, I see a call to create_disk_util_thread() in backend.c. >> >> i/o still seems to be running, and there are no messages in dmesg about >> hung i/o or the scsi mid layer getting angry and trying to abort things >> or anything like that. Seems to be happily cruising along, except that >> the eta isn't updating, and the job should have finished several hours >> ago now. I'm leaving it running for now just to try to figure out >> what happened. >> >> Any ideas? Anything else I should poke at? > > A bit more info: > > thread 26 looks to be the one that's supposed to print the eta info: > > (gdb) thread 26 > [Switching to thread 26 (Thread 0x7f65da431700 (LWP 8531))]#0 0x0000003aa4cacced in nanosleep () from /lib64/libc.so.6 > (gdb) bt > #0 0x0000003aa4cacced in nanosleep () from /lib64/libc.so.6 > #1 0x0000003aa4ce1e44 in usleep () from /lib64/libc.so.6 > #2 0x00000000004474a0 in disk_thread_main (data=) at backend.c:1992 > #3 0x0000003aa50079d1 in start_thread () from /lib64/libpthread.so.0 > #4 0x0000003aa4ce8b5d in clone () from /lib64/libc.so.6 > (gdb) > > static void *disk_thread_main(void *data) > { > int ret = 0; > > fio_mutex_up(startup_mutex); > > while (threads && !ret) { > usleep(DISK_UTIL_MSEC * 1000); > if (!threads) > break; > ret = update_io_ticks(); > > if (!is_backend) > print_thread_status(); > } > > fio_mutex_up(disk_thread_mutex); > return NULL; > } > > that usleep() is where it's in nanosleep, I guess. > > from eta.c: > > void print_thread_status(void) > { > struct jobs_eta *je; > size_t size; > > je = get_jobs_eta(0, &size); > if (je) > display_thread_status(je); > > free(je); > } > > Maybe that je is coming back false? which is > probably the return value of calc_thread_status() which, well, > at a glance, I'm not sure what calc_thread_status() is doing. I'll take a look at this next week, been away at a conference since last weekend. -- Jens Axboe