Re: net namespace plans for 2.6.25 (was Re: Pid namespaces problems)

[Daniel Lezcano <dlezcano-NmTC/0ZBporQT0dZR+AlfA@public.gmane.org>]

Denis V. Lunev wrote:
 > Daniel Lezcano wrote:
 >> Denis V. Lunev wrote:
 >>> Daniel Lezcano wrote:
 >>>
 >>>>  * the first one is the locking of the network namespace list by
 >>>> rtnl_lock, so from the timer callback we can not browse the network
 >>>> namespace list to check the age of the routes. It is a problem I would
 >>>> like to talk with Denis if he has time
 >>> From my point of view, the situation is clear. The timer should be
 >>> per/namespace. The situation is completely different as one in IPv4.
 >> We thought to make a timer per namespace for ipv6, but we are a little
 >> afraid for the performances when there will be a lot of containers.
 >> Anyway, we can do a timer per namespace and optimize that later. I will
 >> cook a new patch to take into account that for the next week.
 >
 > IMHO not a problem. tcp_write_timer is per/socket timer. If this works
 > efficiently, per/namespace one will work also.

That's right, this is a good argument. By the way, the amount of work to 
be done in the tcp_write_timer is perhaps smaller than the one done in 
the ipv6 routing age check, no ? Anyway, I'm not against a timer per 
namespace in this case, I already did a try before rolling back to a 
for_each_net in the gc timer, that changes a little the API, but nothing 
we can handle easily.