Hi, we're running some performance tests against some clusters and I'm
curious about some of the numbers I see.
I'm running the stress test against two identically configured clusters, but
after I run at stress test, I get different Load values across the
clusters?
The difference between the two clusters is that one uses standard EC2
interfaces, but the other runs on a virtual network. Are these differences
indicating something that I should be aware of??
Here is a sample of the kinds of results I'm seeing.
Address DC Rack Status State Load Owns
Token
12760588759xxx
10.0.0.17 DC1 RAC1 Up Normal 94 MB
25.00% 0
10.0.0.18 DC1 RAC1 Up Normal 104.52 MB
25.00% 42535295865xxx
10.0.0.19 DC1 RAC1 Up Normal 78.58 MB
25.00% 85070591730xxx
10.0.0.20 DC1 RAC1 Up Normal 78.58 MB
25.00% 12760588759xxx
Address DC Rack Status State Load Owns
Token
12760588759xxx
10.120.35.52 DC1 RAC1 Up Normal 103.74 MB
25.00% 0
10.120.6.124 DC1 RAC1 Up Normal 118.99 MB
25.00% 42535295865xxx
10.127.90.142 DC1 RAC1 Up Normal 104.26 MB
25.00% 85070591730xxx
10.94.69.237 DC1 RAC1 Up Normal 75.74 MB
25.00% 12760588759xxx
The first cluster with the vNet (10.0.0.0/28 addresses) consistently show
smaller Load values. The total Load of 355MB vs. 402MB with native EC2
interfaces?? Is a total Load value even meaningful?? The stress test is the
very first thing that's run against the clusters.
[I'm also a little puzzled that these numbers are not uniform within the
clusters, but I suspect that's because the stress test is using a key
distribution that is Gaussian. I'm not 100% sure of this either since I've
seen conflicting documentation. Haven't tried 'random' keys, but I presume
that would change them to be uniform]
Except for these curious Load numbers, things seem to be running just fine.
Getting good fast results. Over 10 iterations I'm getting more than 10-12K
inserts per sec. (default values for the stress test).
Should I expect the Load to be the same across different clusters?? What
might explain the differences I'm seeing???
Thanks in advance.
CM
