Using fio 1.23: [root@max13 tmp]# fio myconfigfile Segmentation fault (core dumped) Where myconfigfile is the following: [global] bsrange=64k-128k,64k-128k direct=1 ioengine=libaio iodepth=2 zonesize=256m zoneskip=2g [/dev/exa/g1/v1] rw=read write_bw_log read-bw write_lat_log read-lat [/dev/exa/g1/v1] stonewall rw=write write_bw_log write-bw write_lat_log write-lat Note: removing one or the other parameter to write_*_log reports an error like "Bad option write_lat_log read-lat" but letting both of them segfault. I did this syntaxe as the man page says : write_bw_log If given, write bandwidth logs of the jobs in this file. I thought that "this file" meant a parameter. Cheers, -- Erwan Velu Pre-Sales Engineer Seanodes http://www.seanodes.com +33 (0)1 41 22 13 83 -- 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