[infinispan-dev] Performance gap between different value sizes and between key loactions

[linjunru]

Hi, all:
         I have tested infinispan in distributed mode in terms of latency of put(k,v) operation. The own_num is 1 and the key we put/write locates in the same node as the put operation occurs(In the table,“1+0” represents this scenario),  the results indicates that the latency increases as the size of the value increases. However the increments seem to be a little “unreasonable” to me, because the bandwidth of the memory system is quite huge, and the number of keys (10000) remains the same during the experiment. So, here is the questions: which operations inside infinspan have strong relatives with the size of value, and why they costs so much as the size increases?
         We have also tested infinispan in the scenario which the key and the put/write(key,value) operation reside in different nodes(we noted it as “0+1”). Compared with “1+0”, “0+1” triggers network communications, however, the network latency is much smaller compared to the performance gas between the two scenarios. Why this situation happens? For example, with a 25K bytes ping packet, the RTT is about 0.713ms while performance gas between the two scenarios is about 8.4ms，what operations inside infinispan used the other 7.6ms?
         UDP is utilized as the transport protocol, the infinispan version we used is 7.0  and there are 4 nodes in the cluster, each has 10000 keys, all of them have memory bigger than 32G, and all of them have xeon cpu e5-2407 x2.

Value size

250B( us)

2.5K( us)

25k(us)

250k(us)

2.5M(us)

25M(us)

1+0

463

726

3 236

26 560

354 454

3 979 830

0+1

1 807

2 829

11 635

87 540

1 035 133

11 653 389


         Thanks!

Best Regards,
JR
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