Hey guys,

I've been playing with EvilCraft on the SolitaryCraft dev server. Since the beginning I had around 10 FPS while normally I have 30-60. I narrowed it down to EvilCraft and cross-checked with an clean MC+Forge instance that has only EvilCraft, it's only EvilCraft that is causing the issue.

I know that this isn't terribly helpful, but what I've seen of the mod so far I really like. So if there is anything I can do to help pinpoint the issue, I'll do what I can.

I personally don't have this problem, but I'll try to help.
I presume you are using EC version 0.5.1? And if so, did you also have this problem with 0.5.0?
Are you having this problem only while doing certain things, like exploring?
And do you have this problem the moment you load the world, or only after a certain time?
What OS are you running?

I'm running 0.5.1, I'll see if I can check an earlier version. I'm playing on Win7 with Java 7.
The issue is ubiquitous. I have it just starting a new world and it doesn't ever get better, no matter what I do or don't do (well, besides the even lower FPS spikes when the world loads/generates of course).
Just to mention it, there is at least one other player on the server with this issue, but also most people are fine (or at least not as bad as we are).

Same issue with 0.5.0.

Ok, thanks for reporting this.
I'll do some profiling to hopefully determine the cause of this problem.

I'm happy to help, feel free to give me test versions to try.

We have found an issue in the EvilCraft source code, which might or might not have been the cause of the FPS spikes, could you please try out the build at http://cl.ly/3G1y0l201V1D?
Unfortunately neither myself nor kroeser can reproduce the FPS lag spikes, so it's hard to figure out if we actually solved the problem (I even tried running minecraft in a crappy virtual windows machine and I didn't have any big issues :/).
If this doesn't seem to fix it, could you please give me a full specification (OS, 32- or 64-bit?, complete java version (up to the update version), wether you are running java 32 or 64 bit, processor specs, amount of total RAM, amount of RAM allocated to minecraft, even wether or not minecraft is running on an SSD or an HDD) of the PC's that seem to have this problem?
Until then we'll keep looking into the problem, but until we can reproduce it, finding a fix will be hard...

Awesome, that fixed it. Thanks a lot!

Nice, just to be sure: could you try this dev build out on your dev server for a while (just use it on the client side on the computers that were having the framerate issues, the server shouldn't update).
We should bring out an official update soon, but in the meantime you can use this dev-build.
Also, if you guys have any suggestions or need any further help feel free to contact us directly, we'd love to have some feedback coming from modpack creators/maintainers, especially the packs we like ourselves ;)

Sure, will do =)