RE: [PATCH 0/7] devcg: device cgroup extension for rdma resource

[Hefty, Sean]

> > Trying to limit the number of QPs that an app can allocate,
> > therefore, just limits how much of the address space an app can use.
> > There's no clear link between QP limits and HW resource limits,
> > unless you assume a very specific underlying implementation.
> 
> Isn't that the point though? We have several vendors with hardware
> that does impose hard limits on specific resources. There is no way to
> avoid that, and ultimately, those exact HW resources need to be
> limited.

My point is that limiting the number of QPs that an app can allocate doesn't necessarily mean anything.  Is allocating 1000 QPs with 1 entry each better or worse than 1 QP with 10,000 entries?  Who knows?

> If we want to talk about abstraction, then I'd suggest something very
> general and simple - two limits:
>  '% of the RDMA hardware resource pool' (per device or per ep?)
>  'bytes of kernel memory for RDMA structures' (all devices)

Yes - this makes more sense to me.

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