What does Java option -Xmx stand for? [duplicate]

see here: Java Tool Doc, it says,

-Xmxn
Specify the maximum size, in bytes, of the memory allocation pool. This value must a multiple of 1024 greater than 2MB. Append the letter k or K to indicate kilobytes, or m or M to indicate megabytes. The default value is 64MB. The upper limit for this value will be approximately 4000m on Solaris 7 and Solaris 8 SPARC platforms and 2000m on Solaris 2.6 and x86 platforms, minus overhead amounts. Examples:

           -Xmx83886080
           -Xmx81920k
           -Xmx80m

So, in simple words, you are setting Java heap memory to a maximum of 1024 MB from the available memory, not more.

Notice there is NO SPACE between -Xmx and 1024m

It does not matter if you use uppercase or lowercase. For example: “-Xmx10G” and “-Xmx10g” do the exact same thing.

Related Posts:

  1. How to format strings in Java
  2. What exactly is Apache Camel?
  3. What is an instance variable in Java?
  4. How does the Java ‘for each’ loop work?
  5. How does the Java ‘for each’ loop work?
  6. What does “Could not find or load main class” mean?
  7. How do I create a file and write to it?
  8. When to use LinkedList over ArrayList in Java?
  9. How to convert a char to a String?
  10. How do you create a dictionary in Java? [closed]
  11. How do I declare and initialize an array in Java?
  12. Convert list to array in Java [duplicate]
  13. Convert String to double in Java
  14. How do I generate random integers within a specific range in Java?
  15. “Exception in thread “main” java.lang.IndexOutOfBoundsException: Index: 0, Size: 0″ with ArrayList?
  16. Raising a number to a power in Java
  17. Running JAR file on Windows 10
  18. Iterate through a HashMap [duplicate]
  19. Unfortunately MyApp has stopped. How can I solve this?
  20. exception in thread ‘main’ java.lang.NoClassDefFoundError:
  21. java.io.FileNotFoundException: the system cannot find the file specified
  22. How to parse this string in Java?
  23. How to match “any character” in regular expression?
  24. Double array initialization in Java
  25. I want to declare an empty array in java and then I want do update it but the code is not working
  26. Convert java.util.Date to String
  27. How do I do a deep copy of a 2d array in Java?
  28. Returning an empty array
  29. Java Security: Illegal key size or default parameters?
  30. Could not reserve enough space for object heap
  31. Eclipse: Java was started but returned error code=13
  32. Why java unknown: import org.apache.commons.codec.binary.Base64;?
  33. Extracting .jar file with command line
  34. Unable to create requested service [org.hibernate .engine.jdbc.env.spi.JdbcEnvironment]-MySQL
  35. Why do I get “Exception; must be caught or declared to be thrown” when I try to compile my Java code?
  36. Check jdk/JRE is installed and get path for jvm.dll
  37. What is Java String interning?
  38. Rename a file using Java
  39. JRE 1.7 – java version – returns: java/lang/NoClassDefFoundError: java/lang/Object
  40. Good Java graph algorithm library?
  41. Integrate Ant builder into Eclipse: Error “Variable references empty selection”
  42. Spring Maven clean error – The requested profile “pom.xml” could not be activated because it does not exist
  43. Java Class File Editor
  44. Error Importing SSL certificate : Not an X.509 Certificate
  45. How do I draw a triangle?
  46. warning: [options] bootstrap class path not set in conjunction with -source 1.5
  47. “Actual or formal argument lists differs in length”
  48. Static Block in Java
  49. What does Scanner input = new Scanner(System.in) actually mean?
  50. Class ‘Room’ is abstract; cannot be instantiated
  51. Creating a maze solving algorithm in Java
  52. IDEA: javac: source release 1.7 requires target release 1.7
  53. Can we write our own iterator in Java?
  54. local variables referenced from a lambda expression must be final or effectively final
  55. java.lang.IllegalMonitorStateException: object not locked by thread before wait()?
  56. WebServlet cannot be resolved to a type
  57. How do I print out the value of this boolean? (Java)
  58. How to add an object to an ArrayList in Java
  59. Getting warning “NDK is missing a ‘platforms” directory.’ with no NDK
  60. No appenders could be found for logger(log4j)?
  61. Why am i getting ” Duplicate modifier for the type Test” and how to fix it
  62. Picked up _JAVA_OPTIONS: -Xmx256M
  63. When to use static methods
  64. How to serialize an object into a string
  65. Getting the array length of a 2D array in Java
  66. Java String to SHA1
  67. How do I call one constructor from another in Java?
  68. Does Java have something like C#’s ref and out keywords?
  69. How to upload a file and JSON data in Postman?
  70. What is the difference between i++ & ++i in a for loop?
  71. when to throw FileNotFoundException
  72. How to use ArrayUtils for array of objects, it doesn’t delete the content of an array
  73. The ResourceConfig instance does not contain any root resource classes
  74. Which exception to throw for invalid input which is valid from client perspective
  75. Exception in thread “AWT-EventQueue-0”?
  76. Get Mouse Position
  77. Error: Could not find or load main class net.minecraft.launchwrapper.Launch when launching Minecraft 1.12.2 with Forge
  78. IllegalArgumentException: Bound must be positive
  79. Eclipse is executing the wrong Java file
  80. Understanding BufferedImage.getRGB output values
  81. What is the purpose of creating static object in Java?
  82. How to print a method in java
  83. build-impl.xml:1031: The module has not been deployed
  84. Spring-Security-Oauth2: Full authentication is required to access this resource
  85. Why is System.out.print() not working?
  86. setMnemonic() and call a method by pressing the key
  87. What is `AnyType` in java generics
  88. “insufficient memory for the Java Runtime Environment ” message in eclipse
  89. How to ping an IP address
  90. Java Not Greater than Or Equal to Operator for Char Type
  91. The request was rejected because no multipart boundary was found in springboot
  92. Maven dependency update on commandline
  93. The import javax.servlet can’t be resolved 
  94. Java- The meaning of >?
  95. Where can I download the jar for org.apache.http package?
  96. Java – ‘ ) ‘ expected error
  97. What is the size of a boolean variable in Java?
  98. Use CSS in Java Applications
  99. java.lang.ArrayIndexOutOfBoundsException: 2 [duplicate]
  100. Fastest way to put contents of Set to a single String with words separated by a whitespace?

Leave a Comment

tech