Why is IntelliJ 13 IDEA so slow after upgrading from version 12?

Question

While using IntelliJ 13 ultimate edition for a week, it just seems really slow.

First of all, the whole IDE stops for a second or so every once in a while. The Java

Answer 1

Best experience with following options (idea64.exe.vmoptions):

    -server
    -Xms1g
    -Xmx3g
    -Xss16m
    -XX:NewRatio=3

    -XX:ReservedCodeCacheSize=240m
    -XX:+UseCompressedOops
    -XX:SoftRefLRUPolicyMSPerMB=50

    -XX:ParallelGCThreads=4
    -XX:+UseConcMarkSweepGC
    -XX:ConcGCThreads=4

    -XX:+CMSClassUnloadingEnabled
    -XX:+CMSParallelRemarkEnabled
    -XX:CMSInitiatingOccupancyFraction=65
    -XX:+CMSScavengeBeforeRemark
    -XX:+UseCMSInitiatingOccupancyOnly

    -XX:MaxTenuringThreshold=1
    -XX:SurvivorRatio=8
    -XX:+UseCodeCacheFlushing
    -XX:+AggressiveOpts
    -XX:-TraceClassUnloading
    -XX:+AlwaysPreTouch
    -XX:+TieredCompilation

    -Djava.net.preferIPv4Stack=true
    -Dsun.io.useCanonCaches=false
    -Djsse.enableSNIExtension=true
    -ea