[dpdk-dev] [PATCH] mbuf: replace c memcpy code semantics with optimized rte_memcpy

[Hunt, David]

On 5/24/2016 4:17 PM, Jerin Jacob wrote:
> On Tue, May 24, 2016 at 04:59:47PM +0200, Olivier Matz wrote:
>
>> Are you seeing some performance improvement by using rte_memcpy()?
> Yes, In some case, In default case, It was replaced with memcpy by the
> compiler itself(gcc 5.3). But when I tried external mempool manager patch and
> then performance dropped almost 800Kpps. Debugging further it turns out that
> external mempool managers unrelated change was knocking out the memcpy.
> explicit rte_memcpy brought back 500Kpps. Remaing 300Kpps drop is still
> unknown(In my test setup, packets are in the local cache, so it must be
> something do with __mempool_put_bulk text alignment change or similar.
>
> Anyone else observed performance drop with external poolmanager?
>
> Jerin

Jerin,
     I'm seeing a 300kpps drop in throughput when I apply this on top of 
the external
mempool manager patch. If you're seeing an increase if you apply this 
patch first, then
a drop when applying the mempool manager, the two patches must be 
conflicting in
some way. We probably need to investigate further.
Regards,
Dave.