I am running a cluster consisting of 22 nodes.
(22 nodes under the same 1Gbps switch.)
I noticed some nodes in the cluster has higher "frame" value in ifconfig like the following.
some nodes (higher frame): eth0 Link encap:Ethernet HWaddr 90:B1:1C:09:D2:F8 inet addr:192.168.121.20 Bcast:192.168.121.255 Mask:255.255.255.0 inet6 addr: fe80::92b1:1cff:fe09:d2f8/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:643150667 errors:0 dropped:790 overruns:0 frame:280072 TX packets:908361364 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:377424658828 (351.5 GiB) TX bytes:864099883266 (804.7 GiB) Interrupt:170 Memory:d91a0000-d91b0000 other nodes (lower frame): eth0 Link encap:Ethernet HWaddr 24:B6:FD:F6:DF:34 inet addr:192.168.121.3 Bcast:192.168.121.255 Mask:255.255.255.0 inet6 addr: fe80::26b6:fdff:fef6:df34/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:1126524649 errors:0 dropped:118 overruns:0 frame:43775 TX packets:847071691 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:992080311726 (923.9 GiB) TX bytes:385366462299 (358.9 GiB) Interrupt:170 Memory:d91a0000-d91b0000
What might be wrong with it ?
I also ran ethtool and
"rxbds_empty" matches "frame" in ifconfig and "rx_discards" matches "dropped" in ifconfig.
what is rxbds_empty and rx_discards ?
I have investigated those, but there is almost no information about it.
Are they coming from something bad configuration or setting ?
The weird thing is newly added 6 nodes have that higher value.
Also, I noticed some program runs slower than before we added those 6 nodes.
What the program is doing is that every node requests huge amount of short messages to other random nodes in parallel.
Ideally, every node has the some completion time with the program, but the added 6 nodes run slower than others.
Could anyone give me any advice ? Any help will be appreciated.