From a35ee541a66d11d26da30d3f6046dbddd073334e Mon Sep 17 00:00:00 2001 From: Yevgeny Petrilin Date: Thu, 6 Aug 2009 19:27:28 -0700 Subject: mlx4_en: Adaptive moderation policy change If the net device is identified as "sender" (number of sent packets is higher then the number of received packets and the incoming packets are small), set the moderation time to its low limit. We do it because the incoming packets are acks, and we don't want to delay them Signed-off-by: Yevgeny Petrilin Signed-off-by: David S. Miller --- drivers/net/mlx4/en_netdev.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/net/mlx4/en_netdev.c b/drivers/net/mlx4/en_netdev.c index 93f4abd990a9..c8a24dcca762 100644 --- a/drivers/net/mlx4/en_netdev.c +++ b/drivers/net/mlx4/en_netdev.c @@ -414,6 +414,7 @@ static void mlx4_en_auto_moderation(struct mlx4_en_priv *priv) unsigned long avg_pkt_size; unsigned long rx_packets; unsigned long rx_bytes; + unsigned long rx_byte_diff; unsigned long tx_packets; unsigned long tx_pkt_diff; unsigned long rx_pkt_diff; @@ -437,6 +438,8 @@ static void mlx4_en_auto_moderation(struct mlx4_en_priv *priv) rx_pkt_diff = ((unsigned long) (rx_packets - priv->last_moder_packets)); packets = max(tx_pkt_diff, rx_pkt_diff); + rx_byte_diff = rx_bytes - priv->last_moder_bytes; + rx_byte_diff = rx_byte_diff ? rx_byte_diff : 1; rate = packets * HZ / period; avg_pkt_size = packets ? ((unsigned long) (rx_bytes - priv->last_moder_bytes)) / packets : 0; @@ -447,10 +450,13 @@ static void mlx4_en_auto_moderation(struct mlx4_en_priv *priv) /* If tx and rx packet rates are not balanced, assume that * traffic is mainly BW bound and apply maximum moderation. * Otherwise, moderate according to packet rate */ - if (2 * tx_pkt_diff > 3 * rx_pkt_diff || - 2 * rx_pkt_diff > 3 * tx_pkt_diff) { + if (2 * tx_pkt_diff > 3 * rx_pkt_diff && + rx_pkt_diff / rx_byte_diff < + MLX4_EN_SMALL_PKT_SIZE) + moder_time = priv->rx_usecs_low; + else if (2 * rx_pkt_diff > 3 * tx_pkt_diff) moder_time = priv->rx_usecs_high; - } else { + else { if (rate < priv->pkt_rate_low) moder_time = priv->rx_usecs_low; else if (rate > priv->pkt_rate_high) -- cgit v1.2.3