I have been working on a project for a client involving building a nodejs cluster. I am trying to get a handle on what the performance characteristics of nodejs should be. I am running the latest stable node, 0.6.13 on Ubuntu 11.10. I am running tests on Amazon EC2 with an "m1.small" and a "c1.medium".
Based on say a 1GHz (m1.small) or 2.5GHz (c1.medium) processor how may concurrent connections should a single nodejs process be able to handle? I start to see strange performance issues when an instance has around 500 concurrent HTTP connections. Instead of performance degrading slowly, there are these strange 1-2 second gaps in performance where something seems to be waiting. For this particular test, I used node's http library for the client load test machine on a "c1.medium", and the nodejs http library again for the server on a different Amazon "c1.medium". I started 1000 concurrent requests simultaneously. Here is a portion of my results that illustrate the issue: Request Number Response Time (ms) Time spent on the Server (ms) 696 818 0 697 818 0 698 819 1 699 3354 1 700 3356 0 701 3358 0 So here at request number 699, you see the response time jump by about 2500ms. The "response time" is what the load tester reads and the "time spent on server" is what the server under test reports as its time spent on the request. Obviously, I realize that if the CPU is busy requests will queue up, but is there any way to get insight into this? Is this a problem with TCP tuning on my linux instance? I have max connections for the instance set to 20,000. Basically, I am trying to figure out how many concurrent connections and/or requests/second a single node process should be able to handle when it is just responding to almost empty HTTP requests. Thanks. -- Job Board: http://jobs.nodejs.org/ Posting guidelines: https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines You received this message because you are subscribed to the Google Groups "nodejs" group. To post to this group, send email to nodejs@googlegroups.com To unsubscribe from this group, send email to nodejs+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/nodejs?hl=en?hl=en
