<div dir="ltr">I've been given a chance to try a high core server (4x10) as a possible RMQ server and have hit a few throughput issues that I hope someone can help shed some light on.<div><br></div><div style>We currently have a decently powered single RMQ server that is running as a standalone node and has RHEL 6.2. It has 12 cores running at 3.4GHz. There are 22 queues, some configured with no-ack, but mostly with acks being used. The message sizes are varied but can get large and we hit about 51k messages/sec throughput through all queues. During the day this system caps out at 63% CPU utilization (13% system) and stays that way until the evening. We are definitely hitting a bottleneck with it. I've tried HiPE in the past, but the system % jumped considerably and we actually got poorer performance and instability.</div>
<div style><br></div><div style>A vendor let us borrow the 40-core machine to see if it would work better. When I switched over to it using the same configuration as the production machine, it capped out at around 12,000 messages/sec. We changed the network card and tweaked MTU to see if that was causing a problem, but it still seems capped. What's odd is I can't determine what is causing the bottleneck on the machine. Each core is only 11-15% utilized. There is no iowait at all. The machine does have a lot more RAM at 256 GB vs 72 GB on the existing hardware. We disabled NUMA in the bios to see if that would change things but we got the same performance. On the producer side that injects the initial data, the logs show it can't push data into the new machine fast enough. There are in-memory queues that store data in case of slow downs and they immediately begin to fill up when pushing to the new machine, whereas it rarely happens with the old one.</div>
<div style><br></div><div style>Are there any other tools that I can use to see why the erlang processes don't seem to be fully utilizing the server's capacity? I know the cores are slower in overall speed, but I would have bet money that in aggregate this machine would outperform our other one. </div>
<div style><br></div><div style>Thanks in advance for any suggestions,</div><div style><br></div><div style> Chris</div></div>