Configuration
BTM configuration settings are stored in a Configuration object. It can be obtained by calling TransactionManagerServices.getConfiguration(). All settings are documented in the javadoc and you should refer to it to know what can be configured.
Contents
How to configure BTM
The Configuration object is implemented with sensible default settings. For a first time user, all default settings are good enough. After the initial testing phase, you might want to change some settings. This can be done in two ways: via a properties configuration file or by setting values directly on the Configuration object.
The properties configuration file
You can create a properties file in which you'll set some configuration settings. All the ones you omit will keep their default value.
The file can be stored anywhere on the file system in which case you need to set the bitronix.tm.configuration system property to tell BTM where the file lies. This is generally done by adding a -D argument to the virtual machine's command line:
java -Dbitronix.tm.configuration=./my-btm-config.properties MyClass
Another way is to call the properties file bitronix-default-config.properties and store it at the root of your classpath.
The properties file is in the default format key=value. Ant-like references (${some.property.name}) to other properties or to system properties (defined with -D on the command line) are supported.
Setting values directly on the Configuration object
You can call any setter you want on the object you get from the call to TransactionManagerServices.getConfiguration(). This is convenient if you do not want to use the properties file to configure BTM but want to leverage - for instance - Spring instead.
Configuration conf = TransactionManagerServices.getConfiguration();
conf.setServerId("jvm-1");
conf.setLogPart1Filename("./tx-logs/part1.btm");
conf.setLogPart2Filename("./tx-logs/part2.btm");
| Read only configuration Once BTM has started, any attempt to call a set method on the |
Since the Configuration object is a singleton, there is no need to pass it to any other object, BTM will pick it up at startup.
| Configuration dropped after restart The |
Configurable settings
There are many different settings that are configurable in the transaction manager. Fortunately, all defaults settings are usually good enough to get started. You only need to tune them when required.
Transaction engine settings
These configurable properties are related to the transaction manager's core.
File property name |
Configuration property name |
Default value |
Description |
|---|---|---|---|
bitronix.tm.serverId |
The machine's IP address but that's unsafe for production usage |
an ASCII ID that must uniquely identify this TM instance. It must not exceed 51 characters or it will be truncated. |
|
bitronix.tm.2pc.async |
false |
Should two phase commit be executed asynchronously ? Asynchronous two phase commit will improve 2PC execution time when there are many resources enlisted in transactions but can be very CPU intensive when used on JDK 1.4 without the java.util.concurrent backport implementation available on the classpath. It also makes debugging more complex. |
|
bitronix.tm.2pc.warnAboutZeroResourceTransactions |
true |
Should transactions executed without a single enlisted resource result in a warning or not ? Most of the time transactions executed with no enlisted resource reflect a bug or a mis-configuration somewhere. |
Disk journal settings
These configurable properties are related to the disk journal used to record recovery information.
File property name |
Configuration property name |
Default value |
Description |
|---|---|---|---|
bitronix.tm.journal.disk.logPart1Filename |
btm1.tlog |
Journal fragment file 1. |
|
bitronix.tm.journal.disk.logPart2Filename |
btm1.tlog |
Journal fragment file 2. |
|
bitronix.tm.journal.disk.forcedWriteEnabled |
true |
Are logs forced to disk ? Do not set to false in production since without disk force, integrity is not guaranteed. |