Re: [Lhms-devel] [PATCH 0/7] Fragmentation Avoidance V19

Avi Kivity
2005-11-01T14:40:09Z

Martin J. Bligh wrote:

>To me, the question is "do we support higher order allocations, or not?".
>Pretending we do, making a half-assed job of it, and then it not working
>well under pressure is not helping anyone. I'm told, for instance, that
>AMD64 requires > 4K stacks - that's pretty fundamental, as just one
>instance. I'd rather make Linux pretty bulletproof - the added feature
>stuff is just a bonus that comes for free with that.
>
>
This particular example doesn't warrant higher-order allocations. We can
easily reserve 8GB of virtual space and map 8K stacks there. This is
enough for 1M threads, and if you want more, there's plenty of virtual
address space where those 8GB came from.

The other common examples (jumbo frames) can probably use
scatter-gather, though that depends on the hardware.