As done for Virtio PMD, this series improves cache utilization of the vhost_virtqueue struct by removing unused field, make the live-migration cache dynamically allocated at live-migration setup time and by moving fields around so that hot fields are on the first cachelines.
With this series, The struct vhost_virtqueue size goes from 832B (13 cachelines) down to 320B (5 cachelines). With this series and the virtio one, I measure a gain of up to 8% in IO loop micro-benchmark with packed ring, and 5% with split ring. I don't have a setup at hand to run PVP testing, but it might be interresting to get the numbers as I suspect the cache pressure is higher in this test as in real use-cases. Changes in v4: ============== - Fix missing changes to boolean (Chenbo) Changes in v3: ============== - Don't check pointer validity before freeing (David) - Don't use deprecated rte_smp_wmb() (David, Checkpatch) - Handle booleans properly (David) - Prevent VQ size field overflow (David) - Fix typo and indent (David) Changes in v2: ============== - Add log_cache freeing in free_vq (Chenbo) Maxime Coquelin (3): vhost: remove unused Vhost virtqueue field vhost: move dirty logging cache out of the virtqueue vhost: optimize vhost virtqueue struct lib/librte_vhost/vhost.c | 21 +++++++++---- lib/librte_vhost/vhost.h | 56 +++++++++++++++++------------------ lib/librte_vhost/vhost_user.c | 44 +++++++++++++++++++-------- lib/librte_vhost/virtio_net.c | 12 ++++---- 4 files changed, 82 insertions(+), 51 deletions(-) -- 2.30.2
