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Connection Option Descriptions : JVM Arguments
  

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JVM Arguments

Attribute

JVMArgs (JVMA)

Purpose

A string that contains the arguments that are passed to the JVM that the driver is starting. The location of the JVM must be specified on the driver library path. For information on setting the location of the JVM in your environment, see:
*Setting the Library Path Environment Variable (Windows)
*Setting the Library Path Environment Variable (UNIX and Linux).
When specifying the heap size for the JVM, note that the JVM tries to allocate the heap memory as a single contiguous range of addresses in the application’s memory address space. If the application's address space is fragmented so that there is no contiguous range of addresses big enough for the amount of memory specified for the JVM, the driver fails to load, because the JVM cannot allocate its heap. This situation is typically encountered only with 32-bit applications, which have a much smaller application address space. If you encounter problems with loading the driver in an application, try reducing the amount of memory requested for the JVM heap. If possible, switch to a 64-bit version of the application.

Valid Values

string
where:
string
contains arguments that are defined by the JVM. Values that include special characters or spaces must be enclosed in curly braces { } when used in a connection string.

Example

To set the heap size used by the JVM to 256 MB and the http proxy information, specify:
{-Xmx256m -Dhttp.proxyHost=johndoe -Dhttp.proxyPort=808}
To set the heap size to 256 MB and configure the JVM for remote debugging, specify:
{-Xmx256m
-Xrunjdwp:transport=dt_socket, address=9003,server=y,suspend=n -Xdebug}

Default

The default value is determined by the value specified for the SQL Engine Mode connection option:
When SQL Engine Mode is set to 0 - direct (SQLEngineMode=0), the default value is:
-Xmx256m
If the SQL Engine Mode is set to 1 – server (SQLEngineMode=1), the default value is
-Xmx1024m

GUI Tab

SQL Engine tab

See Also

SQL Engine Mode