mlx4: give precise rx/tx bytes/packets counters
mlx4 stats are chaotic because a deferred work queue is responsible
to update them every 250 ms.
Even sampling stats every one second with "sar -n DEV 1" gives
variations like the following :
lpaa23:~# sar -n DEV 1 10 | grep eth0 | cut -c1-65
07:39:22 eth0 146877.00 3265554.00 9467.15 4828168.50
07:39:23 eth0 146587.00 3260329.00 9448.15 4820445.98
07:39:24 eth0 146894.00 3259989.00 9468.55 4819943.26
07:39:25 eth0 110368.00 2454497.00 7113.95 3629012.17 <<>>
07:39:26 eth0 146563.00 3257502.00 9447.25 4816266.23
07:39:27 eth0 145678.00 3258292.00 9389.79 4817414.39
07:39:28 eth0 145268.00 3253171.00 9363.85 4809852.46
07:39:29 eth0 146439.00 3262185.00 9438.97 4823172.48
07:39:30 eth0 146758.00 3264175.00 9459.94 4826124.13
07:39:31 eth0 146843.00 3256903.00 9465.44 4815381.97
Average: eth0 142827.50 3179259.70 9206.30 4700578.16
This patch allows rx/tx bytes/packets counters being folded at the
time we need stats.
We now can fetch stats every 1 ms if we want to check NIC behavior
on a small time window. It is also easier to detect anomalies.
lpaa23:~# sar -n DEV 1 10 | grep eth0 | cut -c1-65
07:42:50 eth0 142915.00 3177696.00 9212.06 4698270.42
07:42:51 eth0 143741.00 3200232.00 9265.15 4731593.02
07:42:52 eth0 142781.00 3171600.00 9202.92 4689260.16
07:42:53 eth0 143835.00 3192932.00 9271.80 4720761.39
07:42:54 eth0 141922.00 3165174.00 9147.64 4679759.21
07:42:55 eth0 142993.00 3207038.00 9216.78 4741653.05
07:42:56 eth0 141394.06 3154335.64 9113.85 4663731.73
07:42:57 eth0 141850.00 3161202.00 9144.48 4673866.07
07:42:58 eth0 143439.00 3180736.00 9246.05 4702755.35
07:42:59 eth0 143501.00 3210992.00 9249.99 4747501.84
Average: eth0 142835.66 3182165.93 9206.98 4704874.08
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
4 files changed