I've been using DebugView to debug SBCL code but I've kept bumping into its limitations.
But now I've found a replacement for it - it's the DbgDump. Its main distinction from DebugView is that it's not a GUI program but rather a CLI program that writes into either file, console, or a network socket (using the syslog protocol). Therefore when the debuggee generates thousands of log messages per second, I don't see such a noticeable slowdown.