async-profiler VS heaptrack

We'll use async-profiler and flame graphs for profiling. To simplify the process, we'll run the code using JBang.

JIT'ed code is sadly poorly supported, but LLVM has had great hooks for noting each method that is produced and its address. So you can build a simple mixed-mode unwinder, pretty easily, but mostly in process.

I think Intel's DNN things dump their info out to some common file that perf can read instead, but because the *kernels* themselves reuse rbp throughout oneDNN, it's totally useless.

Finally, can any JVM folks explain this claim about DWARF info from the article:

> Doesn't exist for JIT'd runtimes like the Java JVM

that just sounds surprising to me. Is it off by default or literally not available? (Google searches have mostly pointed to people wanting to include the JNI/C side of a JVM stack, like https://github.com/async-profiler/async-profiler/issues/215).

debugging native calls in itself is also painful. I have switched to using async-profiler (https://github.com/async-profiler/async-profiler) instead of JFR for most of my usecases.

A. it tracks native calls by default

https://github.com/async-profiler/async-profiler#flame-graph...

Ok, Windows is not supported. But IntelliJ made a fork which works on Windows.

Hi, today I used async-profiler to check the CPU usage of my Spring Boot app (just a normal backend) in production. Surprisingly, Lettuce (Redis) + Mybatis (MySQL) take up most of the CPU time. I am not talking about wall time here, but CPU time, since I know database requests need to wait for milliseconds and thus wall time will be very long. Therefore, I wonder:

You can use async-profiler to see what is happening under the hood.

I have used visual vm quite a bit. https://github.com/async-profiler/async-profiler is also amazing... Throw the binary on the system and fire it up. It also profiles down into native code as well if you do that kind of thing.

If we are talking replacing the libc allocator, then something like heaptrack is worth mentioning.

https://github.com/KDE/heaptrack

For accurate memory usage I prefer a memory profiler that overrides malloc and friends instead of the ones that probe the OS at regular intervals. You won't find memory spikes with the latter. Try heaptrack on Linux. I haven't found a good one for Windows yet.

I know it is not a profiler, but it is so criminally underrated that I decided to share it: https://github.com/KDE/heaptrack

If none of the above helps - I recommend heaptrack as a tool for tracking down your memory usage.

> memory leaks. It's surprisingly hard to find an easy to use memory leak detection tool.

I can vouch for heaptrack[1] nowadays, although it's pretty much Linux only. It's under the umbrella of KDE, but a heaptrack trace only requires a CLI app, and there is a nice Qt viewer to analyse the memory consumption.

It tracks the memory utilization at the level of malloc'd/free'd bytes. It's fine if your memory leak or other memory utilization problem is on this level. Recently I dealt with an issue, where increasing memory utilization was caused by fragmentation within the allocator. This didn't show up in heaptrack as an increasing memory utilization, but heaptrack still pointed out where most of the temporary allocations happened, leading to the culprit of the fragmentation.

[1] https://github.com/KDE/heaptrack

This is probably what you are looking for https://github.com/KDE/heaptrack

When I had this kind problems (heap related) I always use heaptrack. Take a look here for the details: https://github.com/KDE/heaptrack