I just installed refined pipes to my modpack and it became unplayable with the mod

I have 4.3 Gb allocated to Mc

How is this a memory issue?

Post the crash report if you are still having issues.

We just downloaded the Valhelsia 2 modpack and we noticed that the memory usage was insane. We used VisualVM to profile the client and we found that the com.raoulvdberge.refinedpipes.render thread was responsible for 1.3 GBs of objects in memory. Here are some screenshots: https://imgur.com/a/vHWuweX

We measured from a client connected to a remote server. We tested in a new world with 0 placed Refined Pipes anywhere. We never even had them in our inventory.

Notice the second screenshot... there are over 1.9 million (!) instances of PipeBakedModels in that thread.

This isn't the kindof thing you can submit a crash report for. We have move RAM than the game is using so the game isn't crashing, and even if we didn't have the RAM, a crash report would just say that the JVM ran out of memory.

I don't pretend to understand how this mod works or how to render things in MC but it seems like that is a problem... We are going to try to do some more investigating though. Thanks!

Thank you, this is actionable and helpful.

This has been fixed for v0.4.2.