Re: XFS unhappy with large holey loopback and syncs

[Steve Lord <lord@xxxxxxx>]

Andi Kleen wrote:
> Yep - on x86-64. But the machine had 8GB of RAM, so if even that
> runs out of memory something is wrong imho. How large allocations
> would it need?
>
> -Andi
28 bytes per extent so in this case rather a lot. This could be
compressed some at the cost of bit manipulation when looking up
extents. I used to rack my brain about how to make xfs work with
a partial in memory extent map.

At least reorganizing the data structure to avoid the large memory
requirement would be good.

You probably didn't see it in the allocator because it was delaying
between retrying the allocate.

Steve