layout IO file is slow

[wangyihanlarry]

I am using FIO to stress the file system with following profiles, there are around 100+ more files in the profile, I found it is pretty to layout the IO file even if I am using the fast allocate, are there any other method to fast the creation of the file?

`[global] ioengine=libaio buffered=0 rw=randrw do_verify=1 verify_fatal=1 verify_dump=1 unlink=1 bs=128k size=512m fallocate=1 directory=/testfs

[file1] size=512m rw=randrw:-8k iodepth=22

[file2] size=1125m rw=randrw:-8k iodepth=15`