[dpdk-dev] [PATCH] eal: fix rte_memcpy perf in hsw/bdw

[Thomas Monjalon]

2016-05-24 21:23, Zhihong Wang:
> This patch fixes rte_memcpy performance in Haswell and Broadwell for
> vhost when copy size larger than 256 bytes.
> 
> It is observed that for large copies like 1024/1518 ones, rte_memcpy
> suffers high ratio of store buffer full issue which causes pipeline
> to stall in scenarios like vhost enqueue. This can be alleviated by
> adjusting instruction layout. Note that this issue may not be visible
> in micro test.
> 
> How to reproduce?
> 
> PHY-VM-PHY using vhost/virtio or vhost/virtio loop back, with large
> packets like 1024/1518 bytes ones. Make sure packet generation rate
> is not the bottleneck if PHY-VM-PHY is used.
> 
> Signed-off-by: Zhihong Wang <zhihong.wang at intel.com>

Test report: http://dpdk.org/ml/archives/dev/2016-May/039716.html

Applied, thanks