Re: fio test triggering bad data on ext4

Jens Axboe
2010-06-18T17:36:10Z

On 2010-06-18 17:13, Jens Axboe wrote:
> On 18/06/10 16.59, Eric Sandeen wrote:
>> Eric Sandeen wrote:
>>> Jens Axboe wrote:
>>>> Hi,
>>>>
>>>> I was writing a small fio job file to do writes and read verifies on a
>>>> device. It forks 32 processes, each writing randomly to 4 files with a
>>>> block size between 4k and 16k. When it has written 1024 of those blocks,
>>>> it'll verify the oldest 512 of them. Each block is checksummed for every
>>>> 512b. It uses libaio and O_DIRECT.
>>>>
>>>> It works on ext2 and btrfs. I haven't run it to completion yet, but they
>>>> survive 15-20 minutes just fine. ext4 doesn't even go a full minutes
>>>> before this triggers:
>>>
>>> Jens, can you try XFS too? Since ext3 can't do direct IO to a hole,
>>> (and I'm not sure about btrfs in that regard), ext4 may be most similar
>>> to xfs's behavior on the test ... wondering how it fares.
>>>
>>> Thanks,
>>> -Eric
>>
>> Actually mingming had a patch for direct-io.c which may be related, I'll
>> test that out.
>
> OK, I'll try XFS tonight as well.

XFS fails too.

--
Jens Axboe