jvm jdk 1.6 锁 优化

关闭Biased Locking（偏向锁） 1.6默认开启（针对单线程反复锁优化，多线程高争用场景可考虑关闭）
打开 DoEscapeAnalysis 逃逸分析
打开锁粗化 EliminateLocks

-XX:-UseBiasedLocking -server -XX:+DoEscapeAnalysis -XX:+EliminateLocks  -Xms4096m -Xmx8192m -server

http://chentmin.com/2013/06/12/biased-locking-and-lock-coarsening/
https://mechanical-sympathy.blogspot.co.uk/

Java Tuning White Paper

给出的一些例子

Tuning Example 1: Tuning for Throughput

java -Xmx3800m -Xms3800m -Xmn2g -Xss128k -XX:+UseParallelGC -XX:ParallelGCThreads=20

 Tuning Example 2: Try the parallel old generation collector

java -Xmx3550m -Xms3550m -Xmn2g -Xss128k -XX:+UseParallelGC -XX:ParallelGCThreads=20 -XX:+UseParallelOldGC

Tuning Example 3: Try 256 MB pages

java -Xmx2506m -Xms2506m -Xmn1536m -Xss128k -XX:+UseParallelGC -XX:ParallelGCThreads=20 -XX:+UseParallelOldGC -XX:LargePageSizeInBytes=256m

Tuning Example 4: Try -XX:+AggressiveOpts

java -Xmx3550m -Xms3550m -Xmn2g -Xss128k -XX:+UseParallelGC -XX:ParallelGCThreads=20 -XX:+UseParallelOldGC -XX:+AggressiveOpts -XX:+UseBiasedLocking

Tuning Example 6: Tuning for low pause times and high throughput

java -Xmx3550m -Xms3550m -Xmn2g -Xss128k -XX:ParallelGCThreads=20 -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:SurvivorRatio=8 -XX:TargetSurvivorRatio=90 -XX:MaxTenuringThreshold=31

 Tuning Example 7: Try AggressiveOpts for low pause times and high throughput

java -Xmx3550m -Xms3550m -Xmn2g -Xss128k -XX:ParallelGCThreads=20 -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:SurvivorRatio=8 -XX:TargetSurvivorRatio=90 -XX:MaxTenuringThreshold=31 -XX:+AggressiveOpts

Java SE 6 Performance White Paper