Re: [PATCH 3/6] compcache: TLSF Allocator interface

From: Nitin Gupta
Date: Thu Apr 03 2008 - 13:23:55 EST


On Tue, Mar 25, 2008 at 12:26 AM, Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> wrote:

> Yeah, it also suffers from a horrible coding style, can use excessive
> amounts of vmalloc space, isn't hooked into the reclaim process as an
> allocator should be and has a severe lack of per-cpu data making it a
> pretty big bottleneck on anything with more than a few cores.
>
> Now, it might be needed, might work better, and the scalability issue
> might not be a problem when used for swap, but still, you don't treat
> any of these points in your changelog.
>


I will add these points to changelog.
This project is meant for small systems only. So, scalability is not an issue.


> FWIW, please split up the patches in a sane way. This series looks like
> it wants to be 2 or 3 patches. The first introducing all of TLSF (this
> split per file is horrible). The second doing all of the block device,
> and a possible last doing documentation and such.
>

Ok. I will resend with better splitting.


> Also, how bad was kmalloc() compared to this TLSF, we need numbers :-)
>
>

I have posted performance numbers at:
http://code.google.com/p/compcache/wiki/AllocatorsComparison

Data Summary:

Peak Memory Usage:

* Ideal: 24947 KB
* TLSF: 25377 KB
* KMalloc(SLUB): 36483 KB

So, KMalloc uses ~43% more memory than TLSF!


- Nitin
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