Can we initiliaze a String array of size 1447891223?

Question

I am trying the following code

String[] buffer = new String[1447891223];
Arrays.fill(buffer, "0.0");

The above code gives me java.lang.OutOfMemoryError: Java heap space

Is there any way i could do the above way optimally?

MY sts.ini file have the following configuration

-startup
plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar
--launcher.library
plugins/org.eclipse.equinox.launcher.win32.win32.x86_64_1.1.300.v20150602-1417
-product
org.springsource.sts.ide
--launcher.defaultAction
openFile
--launcher.XXMaxPermSize
512M
-vmargs
-Dosgi.requiredJavaVersion=1.7
-Xms1024m
-XX:MaxPermSize=512m
-Xverify:none
-Dorg.eclipse.swt.browser.IEVersion=10001
-Xmx4000m

does this answer your question ? https://stackoverflow.com/questions/1565388/increase-heap-size-in-java — Eklavya, May 11 '20 at 10:51
Does this answer your question? [Increase heap size in Java](https://stackoverflow.com/questions/1565388/increase-heap-size-in-java) — leopal, May 11 '20 at 10:53
Yes, https://stackoverflow.com/a/3039805/2067492 you can have `Integer.MAX_VALUE - 5` size arrays. — matt, May 11 '20 at 10:55
You have `-Xmx4000m` which sets the max value to 4G, you'll need more space than that. — matt, May 11 '20 at 10:56

score 0 · Answer 1 · answered May 11 '20 at 10:52

Well, do you really need that many String objects? You will have to use at least ~6GB of memory to have pointers to ~1.5 billion strings. Maybe you wanted a String of 1.5 billion characters? That would be a bit less, but not much.

Also, you will have to provide JVM parameters like -Xmx to increase the size of available memory by JVM

QuickSilver · Answer 2 · 2020-05-11T10:58:08.110

0

You should be able to initialize the array of size 1447891223 with minimum -Xms9g memory. Set one of your VM args as -Xms9g or -Xmx9g

import java.util.Arrays;

public class BigArray {

    public static void main(String[] args) {
        String[] buffer = new String[1447891223];
        Arrays.fill(buffer, "0.0");
    }
}

edited May 11 '20 at 10:58

answered May 11 '20 at 10:56

QuickSilver

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Why would you set the minimum value? – matt May 11 '20 at 10:57
updated the ans with Xmx as well. It better to start with the known minimum memory rather than starting with a too low value. – QuickSilver May 11 '20 at 10:59

Can we initiliaze a String array of size 1447891223?

2 Answers2