Dump RPC stats with JGroups

When using remote procedure calls (RPCs) across a cluster using RpcDispatcher, it would be interesting to know how many RPCs of which type (unicast, multicast, anycast) are invoked by whom to whom.

I added this feature in 3.6.8-SNAPSHOT [1]. The documentation is here: [2].

As a summary, since this feature is costly, it has to be enabled with
probe.sh rpcs-enable-details (and disabled with rpcs-disable-details).

From now on, invocation times of synchronous (blocking) RPCs will be recorded (async RPCs will be ignored).

RPC stats can be dumped with probe.sh rpcs-details:

[belasmac] /Users/bela/JGroups$ probe.sh rpcs rpcs-details

-- sending probe on /224.0.75.75:7500
#1 (481 bytes):
local_addr=C [ip=127.0.0.1:55535, version=3.6.8-SNAPSHOT, cluster=uperf, 4 mbr(s)]
uperf: sync  multicast RPCs=0
uperf: async unicast   RPCs=0
uperf: async multicast RPCs=0
uperf: sync  anycast   RPCs=67480
uperf: async anycast   RPCs=0
uperf: sync  unicast   RPCs=189064
rpcs-details=
D: async: 0, sync: 130434, min/max/avg (ms): 0.13/924.88/2.613
A: async: 0, sync: 130243, min/max/avg (ms): 0.11/926.35/2.541
B: async: 0, sync: 63346, min/max/avg (ms): 0.14/73.94/2.221

#2 (547 bytes):
local_addr=A [ip=127.0.0.1:65387, version=3.6.8-SNAPSHOT, cluster=uperf, 4 mbr(s)]
uperf: sync  multicast RPCs=5
uperf: async unicast   RPCs=0
uperf: async multicast RPCs=0
uperf: sync  anycast   RPCs=67528
uperf: async anycast   RPCs=0
uperf: sync  unicast   RPCs=189200
rpcs-details=
<all>: async: 0, sync: 5, min/max/avg (ms): 2.11/9255.10/4917.072
C: async: 0, sync: 130387, min/max/avg (ms): 0.13/929.71/2.467
D: async: 0, sync: 63340, min/max/avg (ms): 0.13/63.74/2.469
B: async: 0, sync: 130529, min/max/avg (ms): 0.13/929.71/2.328

#3 (481 bytes):
local_addr=B [ip=127.0.0.1:51000, version=3.6.8-SNAPSHOT, cluster=uperf, 4 mbr(s)]
uperf: sync  multicast RPCs=0
uperf: async unicast   RPCs=0
uperf: async multicast RPCs=0
uperf: sync  anycast   RPCs=67255
uperf: async anycast   RPCs=0
uperf: sync  unicast   RPCs=189494
rpcs-details=
C: async: 0, sync: 130616, min/max/avg (ms): 0.13/863.93/2.494
A: async: 0, sync: 63210, min/max/avg (ms): 0.14/54.35/2.066
D: async: 0, sync: 130177, min/max/avg (ms): 0.13/863.93/2.569

#4 (482 bytes):
local_addr=D [ip=127.0.0.1:54944, version=3.6.8-SNAPSHOT, cluster=uperf, 4 mbr(s)]
uperf: sync  multicast RPCs=0
uperf: async unicast   RPCs=0
uperf: async multicast RPCs=0
uperf: sync  anycast   RPCs=67293
uperf: async anycast   RPCs=0
uperf: sync  unicast   RPCs=189353
rpcs-details=
C: async: 0, sync: 63172, min/max/avg (ms): 0.13/860.72/2.399
A: async: 0, sync: 130342, min/max/avg (ms): 0.13/862.22/2.338
B: async: 0, sync: 130424, min/max/avg (ms): 0.13/866.39/2.350

This shows the stats for each member in a given cluster, e.g. number of unicast, multicast and anycast RPCs, per target destination, plus min/max and average invocation times for sync RPCs per target as well.

Probe just become even more powerful! :-)
Enjoy!

[1] https://issues.jboss.org/browse/JGRP-2005
[2] Documentation: http://www.jgroups.org/manual/index.html#_looking_at_details_of_rpcs_with_probe