Hi Jens, I'm running into a crash with fio today, seems to be easily reproducible. [root@msablackburn saperf]# fio --version fio-2.1.11-2-g90811 (top of current git tree.) [root@msablackburn saperf]# fio ./2drive_sdr_verify.fio 4_KiB_RR_drive_r: (g=0): rw=randwrite, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=170 4_KiB_RR_drive_s: (g=0): rw=randwrite, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=170 fio-2.1.11-2-g90811 Starting 2 threads fio: io_u.c:1315: __get_io_u: Assertion `io_u->flags & IO_U_F_FREE' failed.a 58m:59s] Aborted (core dumped) my fio job file looks like this: [root@msablackburn saperf]# cat 2drive_sdr_verify.fio [global] direct=1 ioengine=libaio norandommap randrepeat=0 bs=4096 iodepth=170 #iodepth=96 #numjobs=1 numjobs=1 #numjobs=24 # number_ios=1 # runtime=216000 runtime=3600 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=randwrite verify=crc32c-intel verify_backlog=1m do_verify=1 verify_async=6 verify_async_cpus=0-5 [4_KiB_RR_drive_r] filename=/dev/sdr [4_KiB_RR_drive_s] filename=/dev/sds -- steve -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html