From: Eric Dumazet Date: Mon, 5 Nov 2012 16:20:42 +0000 (+0000) Subject: mlx4: change TX coalescing defaults X-Git-Tag: v3.8-rc1~139^2~424 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=ecfd2ce1a9d5e6376ff5c00b366345160abdbbb7;p=profile%2Fivi%2Fkernel-adaptation-intel-automotive.git mlx4: change TX coalescing defaults mlx4 currently uses a too high tx coalescing setting, deferring TX completion interrupts by up to 128 us. With the recent skb_orphan() removal in commit 8112ec3b872, performance of a single TCP flow is capped to ~4 Gbps, unless we increase tcp_limit_output_bytes. I suggest using 16 us instead of 128 us, allowing a finer control. Performance of a single TCP flow is restored to previous levels, while keeping TCP small queues fully enabled with default sysctl. This patch is also a BQL prereq. Reported-by: Vimalkumar Signed-off-by: Eric Dumazet Cc: Yevgeny Petrilin Cc: Or Gerlitz Acked-by: Amir Vadai Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c index edd9cb8..2b23ca2 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c @@ -870,7 +870,7 @@ static void mlx4_en_set_default_moderation(struct mlx4_en_priv *priv) /* If we haven't received a specific coalescing setting * (module param), we set the moderation parameters as follows: * - moder_cnt is set to the number of mtu sized packets to - * satisfy our coelsing target. + * satisfy our coalescing target. * - moder_time is set to a fixed value. */ priv->rx_frames = MLX4_EN_RX_COAL_TARGET; diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h index 9d27e42..8a5e70d 100644 --- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h +++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h @@ -126,7 +126,7 @@ enum { #define MLX4_EN_RX_COAL_TIME 0x10 #define MLX4_EN_TX_COAL_PKTS 16 -#define MLX4_EN_TX_COAL_TIME 0x80 +#define MLX4_EN_TX_COAL_TIME 0x10 #define MLX4_EN_RX_RATE_LOW 400000 #define MLX4_EN_RX_COAL_TIME_LOW 0