Very interesting result. Sent from my HTC
----- Reply message ----- From: "Jeff Schnitzer" <j...@infohazard.org> To: "Google App Engine" <google-appengine@googlegroups.com> Subject: [google-appengine] Backend performance, compared Date: Wed, Aug 8, 2012 09:10 If you've been reading various threads on this list you know that Richard has been having trouble getting his mobile game to run smoothly on GAE. It's a little unusual because timing is coordinated precisely: * At T+0, all clients submit scores * At T+5s, a reaper process aggregates the scores and builds a result set * At T+10s, all clients fetch scores The question is: Where to submit the score data so that the reaper can fetch and aggregate it? Here's some answers that didn't work: * The datastore. Eventual consistency is too eventual to query for all the scores and get them. * Pull queues. There's too much of a delay between task insertion and when it appears for leasing. * A single backend. One backend cannot handle more than ~80qps. He eventually got a system working reliably, sharded across ten B1 instances, at a cost (beyond other charges) of ~$600/mo. It can collect a couple thousand scores within the 5s deadline (barely). I thought this was insane, so I built a few experiments to see what other technologies can do, using the exact program logic of Richard's collector. Here are the results: The environment: 256MB Rackspacecloud VPS running Ubuntu 10.04.4 LTS The cost: $11/mo The command: ab -c 10000 -n 10000 -r http://theurl (that's 10k requests, all concurrent). Node.js: ~2500 qps. Rock solid through multiple test runs, all complete before the deadline. Java SimpleHTTP: ~2100 qps. Had to bump heap up to 128MB. Python Twisted: ~1600 qps. Failed a lot of requests on most test runs. Python Tornado: ~1500 qps, but rock solid through multiple test runs. So basically, an $11/mo VPS server running Javascript vastly exceeds the capabilities of 10 backends at $60/mo each. Jeff -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appengine@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appengine@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
