1.0.1: Excessive client CPU after playing for half an hour

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New Member
Jul 29, 2019

What is the bug:
An issue that I came across that causes excessive CPU over time... If you have the console window open due to the number of exceptions and other non critical debug info the log quickly builds to huge size (500,000+ lines - and this is with 'minimal' selected) and it seems the memory/CPU load needed to display the console bogged down my system.

With the console open I would use about 3GB more memory and my CPU usage would climb from 15% average to 90% before stuttering would make the game unplayable. My CPU is an i7 3770 so should be easily able to play modded minecraft.

I'm playing client only with the sever running on a local Linux box. The worst offender for generating client log spam (both debug and exceptions) seems to be thaumcraft (in particular a dark node in a totem near my spawn) and Opis (which I had turned on to get to the bottom of why my server was running slow - turns out it was because OpenJVM was installed instead of 'proper' Java)

To be honest I'm not sure if to classify this is a launcher bug (lag with lots of log) or a mod pack bug (too much log spam)...

Mod & Version:

Paste.feed-the-beast.com log:

Can it be repeated:
Yes - just play the pack connected to a server for a long time with the console open...

Known Fix:
workaround - don't play with the console open and everything is fine