[LTP] [RFC PATCH] fallocate05: increase the fallocate and defallocate size

[Cyril Hrubis]

Hi!
> > This change appears seems to be causing fallocate05 test to reliably
> > trigger OOM (out of memory) on my test machine, which has only 256MB
> > RAM.
> >
> 
> Thanks for reporting the failure. We purposely increase the size of
> fallocate
> to reduce interference from metadata changing. But not clear how much
> size should be a proper value for a small system.
> 
> Can you try with decrease the number of FALLOCATE_BLOCKS?
> 
> i.e.
> 
> #define FALLOCATE_BLOCKS 64
> #define DEALLOCATE_BLOCKS 16
> 
> Or, what about other multiple sizes, test result?

Looking at the test I do not think there is a reason to allocate more
than a two or four blocks for the buffer. We just need to write() to the
fallocated area in a loop one block at a time until it's full. I do not
think that it's a good idea to pass ~100MB buffer to a single write()
and expect it to succeed anyways.

-- 
Cyril Hrubis
chrubis@suse.cz