The .properties file for a distributed store contains an option for choosing consistency. The options are STRONG or EVENTUAL consistency you will want to understand the trade-offs between these two modes.The .properties file for a distributed store contains an option for choosing consistency. The options are STRONG or EVENTUAL consistency you will want to understand the trade-offs between these two modes.You can set BigMemory Max driver properties (described in the table below) in the -spring.xml configuration file. Alternatively, you can specify many of these properties in an ehcache.xml configuration file and then specify the path for that file in the -spring.xml configuration file using the ehcacheConfigFile property. If this is done, many of the properties in the spring.xml configuration file will be ignored; the settings derived from the ehcache.xml file will be used instead.Use the storeName-spring.properties file to set configuration properties for the BigMemory Max driver.Using off-heap storage requires setting -XX:MaxDirectMemorySize=. Specify this in the command line for starting the correlator as -J-XX:MaxDirectMemorySize=. The documentation provides recommendations for specifying the value of this property. When you add a correlator to a correlator launch configuration in Software AG Designer, you can select the Maximum Java off-heap storage in Mb option. See Correlator arguments.Property Name | Type / Description | ||
cacheConfiguration | Type: CacheConfiguration Ehcache CacheConfiguration bean, shared by all caches (Tables). Typically used as a compound bean name, for example, cacheConfiguration.overflowToOffHeap. | ||
cacheDecoratorFactory | Type: String Name of a class to use as a cacheDecoratorFactory. The named class must be on the classpath and must implement Ehcache's CacheDecoratorFactory interface. | ||
cacheDecoratorFactoryProperties | Type: Properties Properties to pass to a cacheDecoratorFactory. Allows use of the same class for many caches. | ||
clusterName | Type: String Comma-separated list of host:port identifiers for the servers, or a tc-config.xml file name. Best practice is to list all Terracotta Server Array (TSA) nodes. | ||
configuration | Type: Configuration Ehcache Configuration bean. Typically used as a compound bean name, for example, configuration.monitoring. | ||
maxMBLocalOffHeap | Type: long Number of MB of local off-heap data. Total across all tables, per correlator process. | ||
pinning | Type: String Either an attribute value of "inCache" (default) or "localMemory" or a <null/> XML element (i.e.<property name="pinning"><null/></property>.) Pinning prevents eviction if the cache size exceeds the configured maximum size. Recommended if the cache is being used as a system of record. | ||
terracotta Configuration | Type: Terracotta Configuration Ehcache TerracottaConfiguration bean. Typically used as a compound bean name, for example, terracottaConfiguration.consistency. | ||
ehcacheConfigFile | Type: String Path to an ehcache.xml configuration file.
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Property Name | Type / Description |
backupCopies | Type: int Ignored. Not supported. The number of backups is governed by the TSA topology defined in the BigMemory Max documentation and used to configure the TSA nodes. |
converterConfig.default | Type: RowKeyValueConverter bean Specifies the default converter to be used for all tables which do not explicitly specify a converter. A converter is a bean of type RowKeyValueConverter. It is used to convert non-Apama format Ehcache key/value pairs to Apama format key/value pairs. If not specified, then Apama's default converter is used which assumes that the key/value pairs in Ehcache are in Apama format. For example: <property name="converterConfig.default" ref="MyDefaultConverter"/> See the API Reference for Java (Javadoc) and the samples in the samples\distmemstore\bigmemory\converters directory of your Apama installation for more information about RowKeyValueConverter which can be found in the com.apama.correlator.memstore package. |
converterConfig.byTable | Type: Map(String, RowKeyValueConverter) Per-table converter configuration. If a converter is not specified for a table, the default converter specified by the converterConfig.default property is used. For example: <property name="converterConfig.byTable"> <map> <entry key="SensorTable"> <bean class="SensorDataConverter" /> </entry> </map> </property> |
exposeSearchAttributes | Type: boolean Enable exposing search attributes. If true, then the MemoryStore schema columns are exposed as BigMemory search attributes and are indexed, so that other clients of BigMemory can perform searches on the data set. If exposeSearchAttributesSet is non-empty, then only the named columns are exposed as BigMemory search attributes. See notes below about non-Apama applications accessing the data in a BigMemory cluster. |
exposeSearchAttributesSet | Type: Set(String) Limits the set of columns in each table that should be exposed as search attributes. Entries are in the form tableName.columnName. If empty, all schema columns are exposed as search attributes. There is an incremental cost per column that is exposed, so for performance, only expose the columns which need to be used in searches. For example, to expose only the Surname and FirstName columns of myTable: <property name="exposeSearchAttributes" value="true"/> <property name="exposeSearchAttributesSet"> <set> <value>myTable.Surname</value> <value>myTable.FirstName</value> </set> </property> |
initialMinClusterSize | Type: int The minimum cluster size (number of correlators) that must be connected for prepare to finish. |
logLevel | Type: String The log level. |
rowChangedOldValueRequired | Type: boolean Whether to expose old values in rowChanged events. Must be set to false. |
useCompareAndSwap | Type: boolean Whether to use compare and swap (CaS) operations or just put/remove. Some versions of BigMemory Max support only CaS in Strong consistency. |
useCompareAndSwapMap | Type: Map(String, Boolean) Per-table (cache) configuration for whether to use CaS or put/remove. |
Property Name | Type / Description |
cacheConfiguration.eternal | Type: boolean Disables expiration (removing old, unused values) of entries if true. Set to true in the default spring.xml configuration file. |
cacheConfiguration. maxEntriesLocalHeap | Type: int The number of entries for each table. This is the maxEntriesLocalHeap entry in the .properties file. |
cacheConfiguration. overflowToOffHeap | Type: boolean Whether to use off-heap storage. For scenarios where data is fast changing and being written from multiple correlators, the cache may perform better if this is disabled. This is the cacheConfiguration.overflowToOffHeap entry in the .properties file. |
pinning | Type: String Set to inCache by default. |
terracottaConfiguration. localCacheEnabled | Type: boolean Whether to cache entries in the correlator process. Set to true in the default spring.xml configuration file. |
terracottaConfiguration. clustered | Type: boolean Whether to use a TSA. Set to true in the default spring.xml configuration file. |
terracottaConfiguration. consistency | Type: String Either 'STRONG' or 'EVENTUAL'. STRONG gives MemoryStore-like guarantees, while EVENTUAL is faster but may have stale values read. This is the terracottaConfiguration.consistency entry in the .properties file. |
terracottaConfiguration. synchronousWrites | Type: boolean If true, then data is guaranteed to be out of process by the time a Row.commit() action completes. Disabling this can increase speed. This is the terracottaConfiguration.synchronousWrites entry in the .properties file. |
Note: | When using the BigMemory Max driver, all correlators accessing the same data in a BigMemory cluster must have the same configuration. If accessing from non-Apama applications, clients will need the correct cache configuration (available from the Terracotta Management Console) and have the appropriate Apama classes available on their classpath (available in the distmemstore and ap-distmemstore-bigmemory.jar files) in order to access the cache. |
MemoryStore Event Object | BigMemory Max Class |
Store | CacheManager |
Table | Cache |
Row | Element |
