|
can you post your netstat –s on one of your servers that is having the
problem?
From: Michael Krysiak
Sent: Saturday, June 22, 2013 7:00 AM
Subject: High Latency during packet transmission I've
been trying to identify why we're seeing frequent stalls during packet
transmission in our GPFS cluster in the bnx2 driver (as well as other
NICs/drivers), but I am at the limit of my current knowledge. I used perf
netdev events (as described in http://lwn.net/Articles/397654/) to measure the tx
times, and see spikes such as the following:
dev
len
Qdisc
netdevice
free
em2 98
807740.878085sec
0.002msec
0.061msec
em2 98
807740.878119sec
0.002msec
0.029msec
em2 98
807741.140600sec
0.005msec
0.092msec
em2 65226
807742.763833sec
0.007msec
0.436msec
em2 66
807727.081712sec
0.001msec
16246.072msec
em2 66
807740.882741sec
0.001msec
3457.625msec Based on the source
for netdev-times.py, the "free" column is the difference between
trace_net_dev_xmit() and trace_kfree_skb() in net/core/dev.c, but I'm not sure
how to dig any deeper. Are there any common causes for this
behavior? What's the best way to further break down the time difference
between the xmit and kfree trace points?
_______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies |
_______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
