Re: [PATCH] generic: test which tries to exercise AIO/DIO into unwritten space

["Theodore Ts'o" <tytso@mit.edu>]

On Tue, Mar 02, 2021 at 11:20:06AM +0800, Su Yue wrote:
> But both xfs and ext4 100% fail in v5.12-rc1 with 4k block size and 4k page
> size on x86_64. The test itself should be okay because btrfs passes.
> xfstests-dev version is 8cbc48b460b6 applied this patch. logs are attached.

Hmm, interesting.  Thanks for the report.  I've been running most of
my tests on a GCE VVM (using gce-xfstests) with a 100GB PD-SSD as the
storage device.  I just tried, and it's passing now reliably on both
4k and 1k for me, both on v5.11 and v5.12-rc1.  (Previously it was
failing about 30% of the time on the ext4/1k test scenario, and was
passing 100% on ext4/4k.)

Given your report, I tried running it using KVM (with a NVME ssd as
the back-end storage device), and it's failing 80% of the time using
the 4k block size.

So previously I had assumed that it was passing consistently on with
ext4/4k, but it looks like that it's very much dependent on the
performance of the TEST_DEV.

					- Ted