Re: [Lsf-pc] LSFMMBPF proposal [MM]: Eliminate vmap/vmalloc lock contention

[Uladzislau Rezki <urezki@gmail.com>]

On Fri, Apr 21, 2023 at 02:03:43PM +0200, Michal Hocko wrote:
> On Tue 28-02-23 17:42:43, Uladzislau Rezki wrote:
> > Hello, LSF.
> > 
> > Title: Introduce a per-cpu-vmap-cache to eliminate a vmap lock contention
> > 
> > Description:
> >  Currently the vmap code is not scaled to number of CPU cores in a system
> >  because a global vmap space is protected by a single spinlock. Such approach
> >  has a clear bottleneck if many CPUs simultaneously access to one resource.
> > 
> >  In this talk i would like to describe a drawback, show some data related
> >  to contentions and places where those occur in a code. Apart of that i
> >  would like to share ideas how to eliminate it providing a few approaches
> >  and compare them.
> 
> It's been some time since you brough this up. Has there been any
> progress on the topic? Do you still find it important to discuss it at
> LSFMM?
> 
The idea about sequence was/is:

1) Give an overview on the proposal;
2) Submit patches to address the problem;
3) Start a discussion over lkml with people who are interested in it;
4) Send out a complete solution.

--
Uladzislau Rezki