Megacomet with 1 million queued messages
TL;DR: Comet server with 1 million queued messages, uses ~5% cpu at 1000msgs/sec and 65m RAM, on the smallest EC2 instance.
I've just started the testing of Megacomet on a 64-bit Amazon EC2 micro instance. My first test is to get it running, and see how it goes when queuing up messages (mainly this is because I haven't yet written a test harness to pull the messages off the queue!). I'm very pleased with the results, so here's the summary:
- Setup: 1 manager process, 8 worker processes. 64-bit Amazon linux.
- 1 million messages queued, at 1000 messages per second (!)
- CPU usage was tiny. Maybe 5%? And most of that was the test harness, which would in a real situation be on a different server from your comet server. Also, keep in mind this is the smallest EC2 server you can get.
- Total memory usage was: 65m
- Each worker averaged 8m
I'm really happy with that, both from the perspective of memory usage, and CPU usage. Keep in mind i plan to implement expiry of messages in the queue, so that in reality you'd never get a queue that large, but it's good to know that it'll queue up 1m messages without breaking a sweat.
You can find the code at: https://github.com/chrishulbert/megacomet
Here's the 'top' capture whilst running, to give you an idea of CPU usage. The 'ruby' process was the test harness:
top - 08:11:29 up 1 day, 2:15, 3 users, load average: 0.00, 0.01, 0.05 Tasks: 70 total, 2 running, 68 sleeping, 0 stopped, 0 zombie Cpu(s): 0.7%us, 2.5%sy, 0.0%ni, 96.1%id, 0.0%wa, 0.0%hi, 0.2%si, 0.5%st Mem: 611212k total, 603348k used, 7864k free, 23904k buffers Swap: 0k total, 0k used, 0k free, 433696k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 30333 ec2-user 20 0 28028 2736 1424 R 4.7 0.4 0:02.51 ruby 30202 ec2-user 20 0 8668 340 264 S 3.7 0.1 0:47.10 megamanager 30219 ec2-user 20 0 34132 25m 484 S 1.0 4.2 0:09.63 megacomet 30223 ec2-user 20 0 17104 9040 480 S 0.7 1.5 0:03.33 megacomet 30213 ec2-user 20 0 17104 9044 480 S 0.3 1.5 0:03.39 megacomet 30217 ec2-user 20 0 17104 9044 480 S 0.3 1.5 0:03.30 megacomet
And here's the top capture at the end of the 1 million queued messages, to show the memory usage:
top - 06:28:46 up 1 day, 33 min, 3 users, load average: 0.01, 0.02, 0.05 Tasks: 69 total, 1 running, 68 sleeping, 0 stopped, 0 zombie Cpu(s): 0.0%us, 0.2%sy, 0.0%ni, 99.8%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st Mem: 611212k total, 600784k used, 10428k free, 23840k buffers Swap: 0k total, 0k used, 0k free, 436568k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 30219 ec2-user 20 0 32548 23m 484 S 0.0 4.0 0:09.03 megacomet 942 root 39 19 324m 14m 1688 S 0.0 2.5 0:00.00 yum-updatesd 30213 ec2-user 20 0 16576 8516 480 S 0.0 1.4 0:03.18 megacomet 30217 ec2-user 20 0 16576 8516 480 S 0.0 1.4 0:03.09 megacomet 30225 ec2-user 20 0 16576 8516 480 S 0.0 1.4 0:03.07 megacomet 30227 ec2-user 20 0 16576 8516 480 S 0.0 1.4 0:03.16 megacomet 30223 ec2-user 20 0 16576 8512 480 S 0.0 1.4 0:03.11 megacomet
