OK, to begin with. I haven't started to trace the bug yet, I just want to confirm if I am the only one or not.
I use MMC 5 to install all mods and handle different instances of MC.
I have in MMC set Java up to use up to 768 MB.
If I play MC 1.7.2 with any 1.7.2 (any I tried, starting back at some late 900er) forge version and Optifine 1.7.2 HD (no other mod installed at that point) after some time (usually several hours) I recognize that my free ram has significant dropped until it is running out at some point. (which results in a very laggy game play and very low frame rate)
So I dunno yet if its caused by minecraft, by optifine, by forge, or by MMC 5.
Is it a known bug?
If it is: Is there a workaround (other than restart MC)?
And why the heck are the forum formatting buttons are currently not working for me? (probably some wired settings in my browser .. which is set up to be so secure it doesn't display any website anymore ;p )