Is there any basic gc generation size and ratios for application in production

开发者_开发问答

How much should be the initial size of the young generation? How much should be -XX:+NewRatio? -XX:+SurvivourRatio? What should be the ratio between perm and old generation.?

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Every application is different. Your best bet is to measure it yourself!

Create an automated test case which runs through a typical use case for your application. Call this from a shell script which creates random permutations of generation sizes, making sure to keep track of how long it runs for with time. Hold on to the fastest 10 and output them when ctrl+c is pressed.

Leave the script running overnight.

You'll have your answer in the morning =)