Hi Jerin,

I just ran a couple of tests on this patch on the latest master head on 
a couple of machines. An older quad socket E5-4650 and a quad socket 
E5-2699 v3

E5-4650:
I'm seeing a gain of 2% for un-cached tests and a gain of 9% on the 
cached tests.

E5-2699 v3:
I'm seeing a loss of 0.1% for un-cached tests and a gain of 11% on the 
cached tests.

This is purely the autotest comparison, I don't have traffic generator 
results. But based on the above, I don't think there are any performance 
issues with the patch.

Regards,
Dave.




On 24/5/2016 4:17 PM, Jerin Jacob wrote:

On Tue, May 24, 2016 at 04:59:47PM +0200, Olivier Matz wrote:

quoted

Hi Jerin,


On 05/24/2016 04:50 PM, Jerin Jacob wrote:

quoted

Signed-off-by: Jerin Jacob <redacted>
---
  lib/librte_mempool/rte_mempool.h | 5 ++---
  1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/librte_mempool/rte_mempool.h b/lib/librte_mempool/rte_mempool.h
index ed2c110..ebe399a 100644
--- a/lib/librte_mempool/rte_mempool.h
+++ b/lib/librte_mempool/rte_mempool.h

@@ -74,6 +74,7 @@
  #include <rte_memory.h>
  #include <rte_branch_prediction.h>
  #include <rte_ring.h>
+#include <rte_memcpy.h>
  
  #ifdef __cplusplus
  extern "C" {

@@ -917,7 +918,6 @@ __mempool_put_bulk(struct rte_mempool *mp, void * const *obj_table,
  		    unsigned n, __rte_unused int is_mp)
  {
  	struct rte_mempool_cache *cache;
-	uint32_t index;
  	void **cache_objs;
  	unsigned lcore_id = rte_lcore_id();
  	uint32_t cache_size = mp->cache_size;

@@ -946,8 +946,7 @@ __mempool_put_bulk(struct rte_mempool *mp, void * const *obj_table,
  	 */
  
  	/* Add elements back into the cache */
-	for (index = 0; index < n; ++index, obj_table++)
-		cache_objs[index] = *obj_table;
+	rte_memcpy(&cache_objs[0], obj_table, sizeof(void *) * n);
  
  	cache->len += n;
  

The commit title should be "mempool" instead of "mbuf".

I will fix it.

quoted

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

quoted

Regards
Olivier