diff options
Diffstat (limited to 'HOWTO')
| -rw-r--r-- | HOWTO | 22 |
1 files changed, 13 insertions, 9 deletions
@@ -976,15 +976,16 @@ write_bw_log=str If given, write a bandwidth log of the jobs in this job filename. For this option, the postfix is _bw.log. write_lat_log=str Same as write_bw_log, except that this option stores io - completion latencies instead. If no filename is given - with this option, the default filename of "jobname_type.log" - is used. Even if the filename is given, fio will still - append the type of log. So if one specifies + submission, completion, and total latencies instead. If no + filename is given with this option, the default filename of + "jobname_type.log" is used. Even if the filename is given, + fio will still append the type of log. So if one specifies write_lat_log=foo - The actual log names will be foo_clat.log and foo_slat.log. - This helps fio_generate_plot fine the logs automatically. + The actual log names will be foo_slat.log, foo_slat.log, + and foo_lat.log. This helps fio_generate_plot fine the logs + automatically. lockmem=int Pin down the specified amount of memory with mlock(2). Can potentially be used instead of removing memory or booting @@ -1008,18 +1009,21 @@ cpuchunks=int If the job is a CPU cycle eater, split the load into disk_util=bool Generate disk utilization statistics, if the platform supports it. Defaults to on. -disable_clat=bool Disable measurements of completion latency numbers. Useful +disable_lat=bool Disable measurements of total latency numbers. Useful only for cutting back the number of calls to gettimeofday, as that does impact performance at really high IOPS rates. Note that to really get rid of a large amount of these calls, this option must be used with disable_slat and disable_bw as well. +disable_clat=bool Disable measurements of completion latency numbers. See + disable_lat. + disable_slat=bool Disable measurements of submission latency numbers. See - disable_clat. + disable_slat. disable_bw=bool Disable measurements of throughput/bandwidth numbers. See - disable_clat. + disable_lat. gtod_reduce=bool Enable all of the gettimeofday() reducing options (disable_clat, disable_slat, disable_bw) plus reduce |