1. I tried to set my heapsize, it gives me an error:

C:\>java -Xms 512M -Xmx 1024M -Xss 1024M
Invalid initial heap size: -Xms
Could not create the Java virtual machine.

2. when setting the above, does values like 512, 512B, 512K work? whats the min and max?

3. Is Conservative collectors faster or slower than normal Garbage collectors?

4. What is generational collection, how does it work differ from reference counting & tracing collection
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

1. >>java -Xms 512M -Xmx 1024M -Xss 1024M

No spaces:

java -Xms512M -Xmx1024M -Xss1024M

2. when setting the above, does values like 512, 512B, 512K work?


>>whats the min and max?

Don't know that there are any - machine dependent

3. That would have to be measured for a particular case

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
jedistarAuthor Commented:
Q1 & Q2, thanks

For 3, i would like to ask, what does conservative collector do exactly?
From: http://java.sun.com/developer/technicalArticles/ALT/RefObj/


Conservative Garbage Collection: If you use the Java Native Interface (JNI) API to make C calls, the garbage collector might see something in memory created by the C code that looks like a pointer, but is actually garbage. In this case, the memory is not garbage collected because the Java VM is conservative and does not reclaim memory that looks like it could be allocated to a pointer.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.