On 04/02/2014 09:23 AM, Mark Nelson wrote:
I've been playing around with usng the various write_*_log options in fio to record run statistics. What I'm finding is that some of the logs have malformed lines in them. The following snippet is from the bw log: 811820, 12263, 0, 4194304 812619, 35929, 0, 4194304 818437, 8448, 0, 419430, 4194304 1256299, 160627, 0, 4194304 1256831, 154274, 0, 4194304 Notice that the malformed line appears to be a partial write that gets truncated. The fio command being used to run the tests is autogenerated, so job files aren't used. here's the one that created the above log snippet: /home/nhm/bin/fio --rw=read --ioengine=libaio --runtime=7200 --ramp_time=0 --numjobs=1 --direct=1 --bs=4194304B --iodepth=16 --size=9216M --write_iops_log=/tmp/cbt/ceph/kvmrbdfio/osd_ra-00004096/client_ra-00000128/op_size-04194304/concurrent_procs-008/iodepth-016/read/output --write_bw_log=/tmp/cbt/ceph/kvmrbdfio/osd_ra-00004096/client_ra-00000128/op_size-04194304/concurrent_procs-008/iodepth-016/read/output --write_lat_log=/tmp/cbt/ceph/kvmrbdfio/osd_ra-00004096/client_ra-00000128/op_size-04194304/concurrent_procs-008/iodepth-016/read/output --time_based --name=/srv/rbdfio-`hostname -s`-0/cbt-kvmrbdfio-0 --name=/srv/rbdfio-`hostname -s`-0/cbt-kvmrbdfio-1 --name=/srv/rbdfio-`hostname -s`-0/cbt-kvmrbdfio-2 --name=/srv/rbdfio-`hostname -s`-0/cbt-kvmrbdfio-3 --name=/srv/rbdfio-`hostname -s`-0/cbt-kvmrbdfio-4 --name=/srv/rbdfio-`hostname -s`-0/cbt-kvmrbdfio-5 --name=/srv/rbdfio-`hostname -s`-0/cbt-kvmrbdfio-6 --name=/srv/rbdfio-`hostname -s`-0/cbt-kvmrbdfio-7 The --numjobs=1 line should be removed, but I believe it gets overridden anyway with multiple name parameters. I wonder if having multiple name parameters (ie multiple fio processes) is causing those processes to all try to write to the same log files, potentially at the same time? Any thoughts would be much appreicated!
What version of fio are you running? -- Jens Axboe -- 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
