19:05:08stassatssimply returning is just 5x faster than calling the old callback, i guess 4x is as good as it gets
19:05:23stassatsmaybe more arguments will win more
19:10:25stassats3 arguments is 5.6x faster, i guess that's not bad then
19:16:30stassatswonder if there can be some non-lisp mode of operations, not registering as a lisp thread, respecting the C calling conventions
19:17:20stassatsso you could have a non-lisp thread talking to C and not being stopped by the GC, but, naturally, it can't touch any movable lisp memory
19:59:07luis`Isn't that how your favorite sbcl feature sb-safepoint works? :)