Documentation > System Stored Procedures > @MarkovUpdate

@NoOp »

@MarkovUpdate

This system procedure will cause every HStoreSite in the cluster to recompute the probabilities of their transaction prediction models. If the the save_to_file input parameter is set to true, then the procedure will write out the updated Markov models to a random file in the HStoreSite’s global.temp_dir.

You can have the BenchmarkController invoke this procedure automatically after the warm-up period of a benchmark by passing in the markov.recompute_warmup parameter, or after the entire benchmark run by passing in the the markov.recompute_end parameter. This will automatically retrieve the written files and combine them into a single MarkovGraphsContainer file that can then be loaded into the system.

Input Parameters

Name Type Description
SAVE_TO_FILE boolean Whether the procedure should write out the update Markov models to a temporary file on disk.

Return Values

Name Type Description
SITE Integer The id of the site that recomputed its models.
PARTITION Integer The id of the partition that recomputed its models.
OUTPUTFILE String The path to file that the HStoreSite saved its updated Markov models for this partition. If save_to_file is false, then this field will be null.
ISGLOBAL Integer Whether or not the Markov models are global (i.e., they are not partitioned with a decision tree). (1 = TRUE, 0 = FALSE)

Java Example

Client client = ClientFactory.createClient();
client = client.createConnection(hostname, port);
ClientResponse cresponse = client.callProcedure("@MarkovUpdate", 1);

Command-Line Example

hstore> EXEC @MarkovUpdate 1

@NoOp »