Identify jdev.conf file in $JDEV_HOME/jdeveloper/jdev/bin ( Eg : C:\Oracle\Middleware\jdeveloper\jdev\bin)
Append below content to jdev.conf file, Save and restart the Jdeveloper
AddVMOption -XX:+AggressiveOpts
AddVMOption -XX:+UseStringCache
AddVMOption -XX:+OptimizeStringConcat
#
# only since Java 6 update 21 performance release
# reduces memory consumption
#
#AddVMOption -XX:+UseCompressedStrings
AddVMOption -XX:+ScavengeBeforeFullGC
#
# only for multi-core machines
#
AddVMOption -XX:+UseConcMarkSweepGC
AddVMOption -XX:+UseGCOverheadLimit
#
# works only on 64-bit JVM
# dramatically reduces memory consumption
# by reducing memory addressing length overhead
#
#AddVMOption -XX:+UseCompressedOops
