Re: ubifs: assertion fails

["Dolev Raviv" <draviv@codeaurora.org>]

> On Tue, 2014-04-01 at 08:52 +0300, Tanya Brokhman wrote:
>> The log isn't flooded with the above mentioned error, but it does repeat
>> several times.
>
> Even though you do a lot of I/O operations?
>
> If the accounting becomes incorrect, I think you'd see a warning for
> each and every I/O operations.

Yes, the log seems clean to me. The error actually occurs while stressing
with iozone benchmark.
Could the error be a result of the corner case you described in your
previous mail.

>
> Also, do you have several UBIFS file-systems mounted?
>

Yes, we have prepared images based on ubifs. So almost all the mounted
partitions are ubifs.

>> Is there any way we can help in debugging and fixing this? Also, we're
>> running on a 3.10 based kernel and I saw a lot of patches that change
>> the shrinker after 3.10 on linux-next. What kernel version did you see
>> the shrinker errors on?
>
> Well, you just need to stress the shrinker. I did it by simply adding a
> hack to ubifs module init which kmalloc()'ed a lot of memory. Not
> too-much, but enough to cause some pressure when doing a lot of I/O
> operations and get UBIFS shrinker be invoked. This took me some amount
> of time to get a good hack. I use a normal PC with some Fedora, and
> nandsime. This makes it a lot easier to debug, comparing with doing this
> on a real target. After all, shrinker is a generic component. I think
> that PC had 4GB of RAM. I do not remember how much I allocated in my
> hack.

I'll probably will take a look at this once I finish other more urgent tasks.
>
> I think I used older version than 3.10 back then.
>
> --
> Best Regards,
> Artem Bityutskiy
>
>


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