[Beowulf] Is it necessary to increase size of the ARP cache?

[Rahul Nabar]

I have seen a few recommendations which recommend increasing the ARP cache
size for networks where more than 512 hosts are on the same IP subnet. e.g.
here:

https://wiki.fysik.dtu.dk/niflheim/System_administration#kernel-arp-cache

But is there a way of knowing from logs etc. if this fix is indeed needed
for my network? I have two different subnets 192.168 and 10.0 each with
approximately 300 servers on them (each server has a low and high speed eth
card and hence the twin subnets)

What is the effect of a suboptimal ARP cache size? Does that affect
the latency of messages too?

-- 
Rahul