In the life of a Java developer every now and then you’ll have one of your apps run out of memory. While this is usually due to poor coding (not closing resources, or managing large files) it helps to know exactly what the defaults are for your system. I had just this need today so went out looking for an answer.
What I found that was the most helpful was this page, but for quick reference here’s how to do it on Windows…
c:\>java -XX:+PrintFlagsFinal -version | findstr /i "HeapSize PermSize ThreadStackSize"
uintx InitialHeapSize := 266634176 {product}
uintx MaxHeapSize := 4267704320 {product}
uintx PermSize = 21757952 {pd product}
uintx MaxPermSize = 85983232 {pd product}
intx ThreadStackSize = 0 {pd product}
java version "1.7.0_40"
Java(TM) SE Runtime Environment (build 1.7.0_40-b43)
Java HotSpot(TM) 64-Bit Server VM (build 24.0-b56, mixed mode)
Note that the values returned are in bytes so throw them into google to convert them into something useful 🙂
Please remember to subscribe to the newsletter to stay up to date!You or someone you know looking to buy or sell?
Disclaimer: Thoughts and opinions are my own, and do not reflect the views of any employer, family member, friend, or anyone else. Some links may be affiliate links, but I don't link to anything I don't use myself. You would think this should be self evident these days, but apparently not...