Re: [patch00/05]: Containers(V2)- Introduction

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wed, 2006-09-20 at 10:38 -0700, Christoph Lameter wrote:
> On Wed, 20 Sep 2006, Rohit Seth wrote:
> 
> > cpusets provides cpu and memory NODES binding to tasks.  And I think it
> > works great for NUMA machines where you have different nodes with its
> > own set of CPUs and memory.  The number of those nodes on a commodity HW
> > is still 1.  And they can have 8-16 CPUs and in access of 100G of
> > memory.  You may start using fake nodes (untested territory) to
> 
> See linux-mm. We just went through a series of tests and functionality 
> wise it worked just fine.
> 

I thought the fake NUMA support still does not work on x86_64 baseline
kernel.  Though Paul and Andrew have patches to make it work.

> > translate a single node machine into N different nodes.  But am not sure
> > if this number of nodes can change dynamically on the running machine or
> > a reboot is required to change the number of nodes.
> 
> This is commonly discussed under the subject of memory hotplug.
> 

So now we depend on getting memory hot-plug to work for faking up these
nodes ...for the memory that is already present in the system. It just
does not sound logical.

> > Though when you want to have in access of 100 containers then the cpuset
> > function starts popping up on the oprofile chart very aggressively.  And
> > this is the cost that shouldn't have to be paid (particularly) for a
> > single node machine.
> 
> Yes this is a new way of using cpusets but it works and we could fix the 
> scalability issues rather than adding new subsystems.
> 

I think when you have 100's of zones then cost of allocating a page will
include checking cpuset validation and different zone list traversals
and checks...unless there is major surgery.

> > And what happens when you want to have cpuset with memory that needs to
> > be even further fine grained than each node.
> 
> New node?
> 

Am not clear how is this possible.  Could you or Paul please explain.

> > Containers also provide a mechanism to move files to containers. Any
> > further references to this file come from the same container rather than
> > the container which is bringing in a new page.
> 
> Hmmmm... Thats is interesting.
> 
> > In future there will be more handlers like CPU and disk that can be
> > easily embeded into this container infrastructure.
> 
> I think we should have one container mechanism instead of multiple. Maybe 
> merge the two? The cpuset functionality is well established and working 
> right.
> 

I agree that we will need one container subsystem in the long run.
Something that can easily adapt to different configurations.

-rohit

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux