Re: XFS unhappy with large holey loopback and syncs

[Andi Kleen <ak@xxxxxxx>]

> Well, since it wants it as a single chunk of kernel memory..... that
> gets hard to do in linux. Actually it probably has one large chunk and
> is doing a realloc to get a larger chunk.

For that it should use vmalloc - also no problem because it is backed
in distributed order 0 4k pages. On 32bit the vmalloc space is a bit limited, 
but 8MB is still only a small part of it On x86-64 it's
VmallocTotal: 34359738367 kB

-Andi