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ubuntuubuntu-18.04iozone

iozone benchmark on zfs ubuntu 18.04 - error: can not open temp file open: invalid argument

I'm testing zfs and other filesystems on ubuntu 18.04 using iozone

command line used: 

iozone -e -I -a -s 100M -r 4k -r 16k -r 512k -r 1024k -r 16384k -i 0 -i 1 -i 2

error:

Can not open temp file: iozone.tmp
open: Invalid argument

The file is there after the error:

-rw-r----- 1 ubuntu ubuntu 0 Jul 21 17:44 iozone.tmp

I've tried setting the folder and tmp file to 0777 and running as root. All result in the same permission error.

Runs fine on the rootfs ssd (ext4 on lvm)

Solution

  • This tipped me off to the solution: https://yaffs.net/lurker/message/20060830.035603.628d8ad0.fi.html

    O_DIRECT doesn't seem to be supported on ZFS on Linux, which makes sense since ZFS performance would be poor without its ARC.

    Removing the -I option gives me some results