I'm using JBoss 4.0.5 and I use the following localDB.properties: #HSQL Database Engine #Wed Jan 17 15:50:01 EST 2007 hsqldb.script_format=0 runtime.gc_interval=0 sql.enforce_strict_size=false hsqldb.cache_size_scale=8 readonly=false hsqldb.nio_data_file=true hsqldb.cache_scale=14 version=1.8.0 hsqldb.default_table_type=memory hsqldb.cache_file_scale=8 hsqldb.log_size=20 modified=no hsqldb.cache_version=1.7.0 hsqldb.original_version=1.8.0 hsqldb.compatible_version=1.8.0 However, I am still seeing the .data file growing without shrinking. I know there is a SET CHECKPOINT DEFRAG cmd, but is there some way you can set in this in the localDB.properties file? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4003042#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...