How to increase heap size for Clojure REPL started from Emacs, either standalone or as a part of a project.
1. Clojure REPL Started for a Lein Project
If you have a Leiningen 2.0 project and start Clojure REPL for it in Emacs via M-x clojure-jack-in then you can set JVM arguments such as heap size in the project.clj:
(defproject cascalog-comoyo "0.1.0-SNAPSHOT" ; ... :jvm-opts ["-Xmx768M"])
2. Clojure REPL Started Outside of Lein
If you use Jake McCrary’s clojure-swank operation to start Clojure REPL in Emacs without having a Leiningen project then you can set JVM options by adding them to the shell-command call in clojure-swank’s definition:
... (shell-command "JAVA_OPTS='-Xmx768M' ~/.lein/bin/swank-clojure &" buffer)) ...