Re: [PATCH v2] mm/slub: disable slab merging in the default configuration

["Julian Pidancet" <julian.pidancet@oracle.com>]

[-- Attachment #1: Type: text/plain, Size: 1393 bytes --]

On Mon Jul 3, 2023 at 02:09, David Rientjes wrote:
> I think we need more data beyond just kernbench.  Christoph's point about 
> different page sizes is interesting.  In the above results, I don't know 
> the page orders for the various slab caches that this workload will 
> stress.  I think the memory overhead data may be different depending on 
> how slab_max_order is being used, if at all.
>
> We should be able to run this through a variety of different benchmarks 
> and measure peak slab usage at the same time for due diligence.  I support 
> the change in the default, I would just prefer to know what the 
> implications of it is.
>
> Is it possible to collect data for other microbenchmarks and real-world 
> workloads?  And perhaps also with different page sizes where this will 
> impact memory overhead more?  I can help running more workloads once we 
> have the next set of data.
>

David,

I agree about the need to perform those tests on hardware using larger
pages. I will collect data if I have the chance to get my hands on one
of these systems.

Do you have specific tests or workload in mind ? Compiling the kernel
with files sitting on an XFS partition is not exhaustive but it is the
only test I could think of that is both easy to set up and can be 
reproduced while keeping external interferences as little as possible.

-- 
Julian

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 265 bytes --]