GH-534: Read heap_size from env variable, if it is available (#538)

* GH-534: Read heap_size from env variable, if it is available

* update changelog

Author: jtnelson

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 #### Version 0.11.7 (TBD)
 * Fixed a bug that made it possible to leak filesystem resources by opening duplicate file descriptors for the same Segment file. At scale, this could prematurely lead to "too many open files" errors.
+* [GH-534](https://github.com/cinchapi/concourse/issues/534): Fixed a bug that caused the `CONCOURSE_HEAP_SIZE` environment variable, if set, not to be read on server startup.
 
 #### Version 0.11.6 (July 6, 2024)
 * Added new configuration options for initializing Concourse Server with custom admin credentials upon first run. These options enhance security by allowing a non-default usernames and passwords before starting the server.

concourse-server/scripts/concourse

@@ -250,7 +250,11 @@ if [ ! -z "$RDP_PREF" ] && [ "$RDP_PREF" -ne "0" ]; then
 fi
 
 #heap_size
-HEAP_PREF=`cat $PREFS | grep -e '^heap_size\s*=\s*[0-9]\{1,\}\(m\|M\|mb\|MB\|g\|G\|gb\|GB\)$' | head -n1 | cut -d'=' -f2 | tr -d ' '`
+if [ ! -z "$CONCOURSE_HEAP_SIZE" ]; then
+  HEAP_PREF=$CONCOURSE_HEAP_SIZE
+else
+  HEAP_PREF=`cat $PREFS | grep -e '^heap_size\s*=\s*[0-9]\{1,\}\(m\|M\|mb\|MB\|g\|G\|gb\|GB\)$' | head -n1 | cut -d'=' -f2 | tr -d ' '`
+fi
 HEAP_PREF=`echo $HEAP_PREF | awk '{print tolower($0)}'`
 HEAP=${HEAP_PREF//[!0-9]/}
 if [[ $HEAP_PREF == *g* ]]; then