NFSd threads amount policy in containers context

[Stanislav Kinsbursky <skinsbursky@parallels.com>]

Hello.
I would like to discuss how to control NFSd threads amount from container environment (is this particular case it means start of NFS server in network namespace 
different to init_net).

So, I see three possible policies (let's assume, that there are two containers - one requested 3 NFSd threads and another one - 4 NFSd threads):
1) start as many threads, as requested. I.e 7 threads for specified case (simplest case, but probably this is to much - 100 containers will start ~800 threads 
by default).
2) start maximum number of requested threads. I.e. 4 threads for specified case (if NFSd server in container, requested 4 threads, will be stopped, then 3 
thread will left working; will require some way to manage - rb tree of sorted list).
3) There could be some other (more flexible) policy: combine second one with running of one more thread for each second and further network namespace, started 
NFS server. I.e.:
1 net ns: 3 threads request = 3 threads started
2 net ns: 4 threads request = 4 + 1 (per-net thread: 1 net ns) = 5 threads started
3 net ns: 8 threads request = 8 + 2 (per-net threads: 2 net ns) = 10 threads started

Bruce and community, what do you think about all this?

-- 
Best regards,
Stanislav Kinsbursky