Re: Using FIO to benchmark Gluster

[Dmitry Antipov <dantipov@cloudlinux.com>]

On 12/21/21 13:21, Seyed Mohammad Fakhraie wrote:

> Thanks Dmitry. As you pointed out, 18446744073709551615 is an
> interesting number. I'm just thinking out loud here and I haven't
> looked at the code yet, could it be caused by an overflow?

Looking through fio sources, my guess is that -1 internally means
"not decided (yet)". Passing -1 via gfapi tells the GlusterFS brick
process to create (size_t)-1 bytes file, which is 2^64 - 1 and not
supported by GlusterFS. Most likely this value is too large for an
underlying filesystem as well (for example, XFS native limit is
2^63 - 1 bytes).

I would suggest to consider simpler scenarios. For example, the
following seems works as expected, and it's quite similar to your
job file:

fio --ioengine=gfapi --volume=test0 --brick=localhost --direct=1 \
     --create_on_open=1 --iodepth=1 --numjobs=1 --bs=4k --size=1G \
     --time_based --runtime=180 --rw=randread --name=test0

Dmitry