Longwing

I've done some additional testing. I was able to reproduce the error in a MultiMC instance of Minecraft 1.5 with Forge 7.7.0.594 installed. The log is different, but the behavior is exactly the same. No drop in frame rate, but a delay of about 5 seconds between action and reaction about once per minute. To eliminate any possibility of a performance issue, I handed the instance 2-4 gigs of ram in setup. As I tested, I also steadily disabled every single graphical setting. By the end of the log file, we're seeing a Graphics: Fast, Render Distance: Tiny, with no clouds, no v-sync, and reduced particles (Keeping in mind that my normal client for actually playing uses Render Far with shaders, and never experiences any problems). Here's the logfile from the test:

Hello, I'm trying to track down an odd error with Forge 6.6.2.534 on Minecraft 1.4.7. I'm aware that the most recent version of forge is 7.7.0.594. However, I'm using the last version available for 1.4.7, which is the version of minecraft that most of the mods I run currently support. Put simply, Minecraft appears to "lag" about once a minute. My frame-rate remains perfectly stable, but all entities in the world freeze, and all changes I make become delayed. After about 5 seconds, the world "catches up", either resetting the changes I make, or applying them all in rapid succession. This issue does not evidence itself on unmodified minecraft installs. Nor does it show up when I install mods that don't depend on forge (I have an independent near-vanilla install with Better Sprinting, Optifine, and SEUS shaders installed, and it runs entirely without issue). I created a test instance using MultiMC to try to narrow down the problem. The log included below is from a brand new instance with only forge installed, no additional mods. System: Software: ForgeModLoader-client-0.log from test install: Of course, I realize that additional testing is warranted. I'll report back on whether 1.5 with the latest version of forge still has the problem, and I'll try getting a completely clean copy of Minecraft without MultiMC set up as soon as I have time, to see if MultiMC is somehow at fault. That said, if anyone has any ideas as to the cause, I'd love to know what I can do to resolve the problem. Thanks for taking the time to look at this error.