According to my server monitoring, my memory usage is creeping up over time:
After ~4 weeks of uptime, it ends up causing problems / crashing (which makes sense, given that I'm on EC2 with m1.large instances => 8GB RAM, and RAM seems to be increasing at about 1.5 GB / week).
If I restart my node.js app, the memory usage resets.
Yet... I'm keeping track of my memory usage via process.memoryUsage(), and even after ~1 week, I'm seeing
{"rss":"693 Mb","heapTotal":"120 Mb","heapUsed":"79 Mb"}
What am I missing? Clearly the leak is in node, yet the process seems to not be aware of it...
You can try node-memwatch module, which helps with leak detection and heap diffing in Node.
Heap diff would look similar to:
{
"before": { "nodes": 11625, "size_bytes": 1869904, "size": "1.78 mb" },
"after": { "nodes": 21435, "size_bytes": 2119136, "size": "2.02 mb" },
"change": { "size_bytes": 249232, "size": "243.39 kb", "freed_nodes": 197,
"allocated_nodes": 10007,
"details": [
{ "what": "String",
"size_bytes": -2120, "size": "-2.07 kb", "+": 3, "-": 62
},
{ "what": "Array",
"size_bytes": 66687, "size": "65.13 kb", "+": 4, "-": 78
},
{ "what": "LeakingClass",
"size_bytes": 239952, "size": "234.33 kb", "+": 9998, "-": 0
}
]
}