public class Slave
extends java.lang.Object
Slave is the main entry point for a slave evaluation process. The slave works with a master process, receiving individuals from the master, evaluating them, and reporting the results back to the master, thus enabling distributed evolution.
Slave replicates most of the functionality of the ec.Evolve class, for example in terms of parameters and checkpointing. This is mostly because it needs to bootstrap and set up the EvolutionState in much the same way that ec.Evolve does. Additionally, depending on settings below, the Slave may act like a mini-evolver on the individuals it receives from the master.
Like ec.Evolve, Slave is run with like this:
java ec.eval.Slave -file parameter_file [-p parameter=value]*
This starts a new slave, using the parameter file parameter_file. The user can provide optional overriding parameters on the command-line with the -p option.
Slaves need to know some things in order to run: the master's IP address and socket port number, whether to do compression, and whether or not to return individuals or just fitnesses. Unfortunately, Sun's CompressedInputStream/CompressedOutputStream is broken (it doesn't allow partial flushes, which is critical for doing compressed network streams). In order to do compression, you need to download the JZLIB library from the ECJ website or from http://www.jcraft.com/jzlib/ . ECJ will detect and use it automatically.
Slaves presently always run in single-threaded mode and receive their random number generator seed from the master. Thus they ignore any seed parameters given to them.
Slaves run in one of three modes:
Parameters
eval.slave-name String |
(the slave's name, only for debugging purposes. If not specified, the slave makes one up.) |
eval.master.host String |
(the IP Address of the master.) |
eval.master.port integer >= 1024 |
(the socket port number of the master.) |
eval.compression bool = true or false (default) |
(should we use compressed streams in communicating with the master?) |
eval.run-evolve bool = true or false (default) |
(should we immediately evaluate the individuals and return them (or their fitnesses), or if we have extra time (defined by eval.runtime), should we do a little evolution on our individuals first?) |
eval.runtime integer > 0 |
(if eval.run-evolve is true, how long (in milliseconds wall-clock time) should we allow the individuals to evolve?) |
eval.return-inds bool = true or false (default) |
(should we return whole individuals or (if false) just the fitnesses of the individuals? This must be TRUE if eval.run-evolve is true.) |
eval.one-shot bool = true (default) or false |
(Should the slave quit when the master quits, or loop continuously in the background processing new masters?) |
Modifier and Type | Field and Description |
---|---|
static java.lang.String |
A_AT
The argument indicating the class where the resource is relative to.
|
static java.lang.String |
A_FILE
The argument indicating that we're starting fresh from a new parameter file.
|
static java.lang.String |
A_FROM
The argument indicating that we're starting fresh from a parameter file stored in a jar file or as some resource.
|
static boolean |
oneShot |
static java.lang.String |
P_EVALCOMPRESSION |
static java.lang.String |
P_EVALMASTERHOST |
static java.lang.String |
P_EVALMASTERPORT |
static java.lang.String |
P_EVALSLAVENAME |
static java.lang.String |
P_MUZZLE |
static java.lang.String |
P_ONESHOT
Should slave go into an infinite loop looking for new masters after the master has quit, or not?
|
static java.lang.String |
P_RETURNINDIVIDUALS |
static java.lang.String |
P_RUNEVOLVE
Should slave run its own evolutionary process?
|
static java.lang.String |
P_RUNTIME
Time to run evolution on the slaves in seconds
|
static java.lang.String |
P_SILENT |
static ThreadPool |
pool |
static boolean |
runEvolve |
static int |
runTime |
static int |
slaveNum
My unique slave number.
|
static int |
SLEEP_TIME
How long we sleep in between attempts to connect to the master (in milliseconds).
|
static byte |
V_EVALUATEGROUPED |
static byte |
V_EVALUATESIMPLE |
static byte |
V_FITNESS |
static byte |
V_INDIVIDUAL |
static byte |
V_NOTHING |
static byte |
V_SHUTDOWN |
Constructor and Description |
---|
Slave() |
Modifier and Type | Method and Description |
---|---|
static void |
evaluateGroupedProblemForm(EvolutionState state,
boolean returnIndividuals,
java.io.DataInputStream dataIn,
java.io.DataOutputStream dataOut) |
static void |
evaluateSimpleProblemForm(EvolutionState state,
boolean returnIndividuals,
java.io.DataInputStream dataIn,
java.io.DataOutputStream dataOut,
java.lang.String[] args) |
static void |
main(java.lang.String[] args) |
public static final java.lang.String P_EVALSLAVENAME
public static final java.lang.String P_EVALMASTERHOST
public static final java.lang.String P_EVALMASTERPORT
public static final java.lang.String P_EVALCOMPRESSION
public static final java.lang.String P_RETURNINDIVIDUALS
public static final java.lang.String P_SILENT
public static final java.lang.String P_MUZZLE
public static final byte V_NOTHING
public static final byte V_INDIVIDUAL
public static final byte V_FITNESS
public static final byte V_SHUTDOWN
public static final byte V_EVALUATESIMPLE
public static final byte V_EVALUATEGROUPED
public static final java.lang.String A_FROM
public static final java.lang.String A_AT
public static final java.lang.String A_FILE
public static final java.lang.String P_RUNTIME
public static int runTime
public static final java.lang.String P_RUNEVOLVE
public static boolean runEvolve
public static final java.lang.String P_ONESHOT
public static boolean oneShot
public static final int SLEEP_TIME
public static final ThreadPool pool
public static int slaveNum
public static void main(java.lang.String[] args)
public static void evaluateSimpleProblemForm(EvolutionState state, boolean returnIndividuals, java.io.DataInputStream dataIn, java.io.DataOutputStream dataOut, java.lang.String[] args)
public static void evaluateGroupedProblemForm(EvolutionState state, boolean returnIndividuals, java.io.DataInputStream dataIn, java.io.DataOutputStream dataOut)