Re: kernel memory allocators

[Lars Heidieker <lars.heidieker%googlemail.com@localhost>]

On Wed, Jan 19, 2011 at 3:57 AM, Allen Briggs <briggs%netbsd.org@localhost> 
wrote:
> On Sun, Jan 16, 2011 at 03:35:17PM +0100, Lars Heidieker wrote:
>> I have got the kmem reworked to be based on the pool allocator
>> directly with different sized caches, backed by the kmem map making
>> it's allocations interrupt save, I replaced the malloc with just a
>> thin wrapper to use the reworked kmem.... system is up and stable.
>
> What are the benefits that you expect to see from doing this work?
> Have you measured to see if those benefits are realized?
>

Benefits I've thought about:
- The kmem pools use pool_caches therefor scalability will be much
better as the old malloc has a single lock for all access, the pools
have one each with a per cpu cache layer.
- The old malloc only returns oversized allocations back to the kmem
layer but nothing that is in it's bucket, pools can be drained...
- Removing one redundant interface in the kernel-api (in the long
term, when dropping the malloc wrapper)

> Do you have your changes available for review?

I am in the progress of some cleanup work, I'll make a patch available
within the next few days.

-- 
Mystische Erklärungen:
Die mystischen Erklärungen gelten für tief;
die Wahrheit ist, dass sie noch nicht einmal oberflächlich sind.
   -- Friedrich Nietzsche
   [ Die Fröhliche Wissenschaft Buch 3, 126 ]