Re: [PATCH 3/12 2.4] e1000 - use vmalloc for data structures not shared with h/w

[Christoph Hellwig <hch@xxxxxxxxxxxxx>]

On Sat, Jul 31, 2004 at 05:38:11PM +1000, Herbert Xu wrote:
> > No, it's not.  vmalloc needs virtual space that's rather limited (e.g. 64MB
> > on PAE x86) in addition to physical memory.  Unless you do really big
> > allocations stay away from vmalloc.
> 
> How big is really big? 64K? 256K? 1M?

Well, the VM deals with big-order (aka bigger than page size) allocations
rather bad, so for allocation during any I/O I'd stick to allocation smaller
than that (and certainly no vmalloc!), for init-time allocations order 1 is
fine, maybe even order 2 or three.