org.hd.d.pg2k.clApp.atHome
Class AHStandaloneMain

java.lang.Object
  org.hd.d.pg2k.clApp.atHome.AHStandaloneMain

public final class AHStandaloneMain
extends java.lang.Object

Core of at-home program: suitable to drive from a bare command-line or better. This can also form the core of a more-sophisticated GUI-based (eg JWS) app.

Author:

dhd

defaultLogger

public static final SimpleLoggerIF defaultLogger

Default logger: writes to stdout.

DEFAULT_SERVER

private static final java.lang.String DEFAULT_SERVER

Default server host name to connect back to; the generic/main host in this case.

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Constant Field Values

DEFAULT_CPU_PERCENT

public static final int DEFAULT_CPU_PERCENT

Default target fractional CPU usage (of entire host) in exclusive range ]1,100[, ie strictly positive. Generally much less than 100% to avoid straining a user system, eg if overclocked or undercooled, and to get reasonable computational return for energy used amortising the base power consumption of the host machine.

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Constant Field Values

DEFAULT_CPU_CHUNK_MS

public static final int DEFAULT_CPU_CHUNK_MS

Default target CPU work chunk in ms; strictly positive. A value from a few hundred milliseconds to a few tens of seconds probably keeps overheads to a reasonably low proportion of CPU time,] and allows slow methods such as minimisation a chance to work.

A sub-1s value may look less weird/lumpy on a user's CPU meter (given a typical 1s sampling on GUI performance meters).

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Constant Field Values

ALLOW_FILESYSTEM_TNCACHE

private static final boolean ALLOW_FILESYSTEM_TNCACHE

If true then attempt to use a primitive filesystem thumbnail/data cache where permitted. This will not be permitted in a JWS environment for example.

This may save a great deal of bandwidth avoiding refetching thumbnails.

The cache may also be prepopulated for stand-alone tests.

This cache is flat, ie contains no subdirectories, and will not be used unless already extant with appropriate permissions.

This may need to be periodically manually cleared of stale/old/bulk/corrupt data, and may become inefficient if it gains many entries.

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Constant Field Values

DEFAULT_TNCACHE_DIR

private static final java.lang.String DEFAULT_TNCACHE_DIR

Default directory in which cache thumbnail/playback data; always relative to pwd/cwd.

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Constant Field Values

PLAYBACK_SAVE_DATA

private static final boolean PLAYBACK_SAVE_DATA

If true then save/record calibration data received from server. Data is saved into a fixed directory where it can easily be retrieved for playback (no-network) mode.

Not viable/safe for JWS mode.

Should not be used (true) when PLAYBACK_NO_NET is true.

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Constant Field Values

PLAYBACK_NO_NET

private static final boolean PLAYBACK_NO_NET

If true then use playback calibration/thumbnail data rather than attempting to connect to the server. This is for stand-alone regression/performance/JVM testing with no network access.

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Constant Field Values

serverHostname

private final java.lang.String serverHostname

Server host name; never null.

log

private final SimpleLoggerIF log

Logger; never null.

percentCPU

private volatile int percentCPU

Target percent CPU usage (of all CPUs in host machine) in exclusive range ]1,100[, ie strictly positive.

chunkMs

private volatile int chunkMs

Target CPU work chunk in ms; strictly positive.

bs

final javax.jnlp.BasicService bs

Handle on JWS basic service; null if none. Package-visible so as to be directly usable by GUI classes.

ps

final javax.jnlp.PersistenceService ps

Handle on JWS persistence service; null if none. Package-visible so as to be directly usable by GUI classes.

fos

final javax.jnlp.FileOpenService fos

Handle on JWS file-open service; null if none. Package-visible so as to be directly usable by GUI classes.

sis

final javax.jnlp.SingleInstanceService sis

Handle on JWS singleton service; null if none. Package-visible so as to be directly usable by GUI classes.

exs

final javax.jnlp.ExtendedService exs

Handle on JWS extended service; null if none. Package-visible so as to be directly usable by GUI classes.

workerThreadPoolDiscardable

private final java.util.concurrent.ThreadPoolExecutor workerThreadPoolDiscardable

Thread pool; reconfigurable at run-time; never null.

lastFetchedCalibrationData

private volatile long lastFetchedCalibrationData

Last time we polled the server for calibration data. Initially zero (indicating "never").

Marked volatile for thread-safe lock-free access.

DATA_BLOCK_START

public static final java.lang.String DATA_BLOCK_START

Start sequence; we look for a line containing this to start our data.

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Constant Field Values

DATA_BLOCK_END

public static final java.lang.String DATA_BLOCK_END

End sequence; we look for a line containing this to start our data.

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Constant Field Values

GETDATA_METHOD

private static final java.lang.String GETDATA_METHOD

Method to use in getData() to connect to server (POST or GET). POST easier to distinguish from normal browser (human) traffic, but may not get through some proxies or firewalls.

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Constant Field Values

_submitLock

private static final java.lang.Object _submitLock

Lock used to serialise new/best Scorer submissions back to the server; never null.

tunnelURL

private final java.lang.String tunnelURL

Full URL for dedicated 'AH' tunnel on server; never null.

fakeTunnel

private final AHStandaloneMain.FakeTunnel fakeTunnel

Synthetic data pipeline tunnel back to server; never null.

cb

private final AHStandaloneMain.Callback cb

Callback object for reporting new/best Scorer; never null.

scorersReported

private final java.util.concurrent.atomic.AtomicInteger scorersReported

Number of Scorers reported back home (ignoring failures); never null, never negative.

lastSAC

private volatile ScoreAndConf lastSAC

Score/confidence of last Scorer reported; never null. Marked volatile for safe lock-free access.

genTimeRemaining

private volatile int genTimeRemaining

Time remaining for this generation; reset if a new/best Scorer is found. Marked volatile for safe lock-free access.

MIN_GENERATION_MS

public static final int MIN_GENERATION_MS

Minimum time (in ms) spent working on one generation; strictly positive. Setting a lower bound on generation time avoids wasting too much bandwidth on the client fetching calibraton data and maximises the chance of a client finding an 'unusual'/rare Scorer, but setting it too high risks wasting client CPU when no more progress can be made.

A value in the range of minutes to hours is probably appropriate.

MIN_SCORER_SERVER_REPORT_GAP_MS

public static final int MIN_SCORER_SERVER_REPORT_GAP_MS

Minimum time between reports back to the server; strictly positive but much less than MIN_GENERATION_MS. This avoids wasteful 'chatter' back to base, but ensures that we should always have time to flush our 'last' result back for a given generation.

Should be small enough to minimise any chance of significant work loss with unexpected shutdown.

pleaseQuit

private volatile boolean pleaseQuit

Set to try to force main loop to quit ASAP, never set back to false. Marked volatile for thread-safe lock-free access.

AHStandaloneMain

AHStandaloneMain(SimpleLoggerIF log)

Create worker instance with all defaults and the supplied logger. Does no work; just stores the parameters.

Package-visible to be exposed only to this package.

AHStandaloneMain

AHStandaloneMain(java.lang.String serverHostname,
                 SimpleLoggerIF log,
                 int percentCPU,
                 int chunkMs)

Create worker instance with the suppied logger and other parameters. Does no work; just stores the parameters.

Package-visible to be exposed only to this package.

main

public static void main(java.lang.String[] args)

Command-line start-up. Takes no arguments.

Writes any log/status information to stdout.

Defaults to take ~50% of available CPU.

Parameters:

args - an optional first argument is interpretted as serverhost[:port]

getCacheDir

private java.io.File getCacheDir()

Get filesystem-based thumbnail/data cache directory, or null if none.

getData

private java.util.List<java.lang.String> getData(java.lang.String tunnelURL,
                                                 java.lang.String dataType,
                                                 java.lang.String q)
                                          throws java.io.IOException

Fetch specified ordered records from server; may be empty but never null. Looks for first block of lines between

and

, extracting each line starting with

and ending with

as a record.

Parameters:

q - if not null, part to pass as the generic (query) parameter (will be URL encoded)

Throws:

java.io.IOException

getCalibrationSet

private Tuple.Pair<java.util.Set<java.lang.String>,java.util.Map<java.lang.String,ScoreAndConf>> getCalibrationSet(java.lang.String tunnelURL,
                                                                                                                   java.lang.String baseName)
                                                                                                            throws java.io.IOException

Get calibration data from server; never null but may be empty.

Parameters:

baseName - valid Scorer base name supported by current cache/population

Returns:

the set of full calibration exhibit names for the given Scorer base type, and the map from the short version of those names to their ScoreAndConf calibration/vote values

Throws:

java.io.IOException

sendNewBestScorer

private static boolean sendNewBestScorer(java.lang.String tunnelURL,
                                         java.lang.String scorerNameAndParameters,
                                         SimpleLoggerIF log)

Send the new Scorer back to the server. We serialise these to never send back more than one at a time to avoid wasting server connection resources.

Parameters:

tunnelURL - the full URL for the tunnel servlet; never null

scorerNameAndParameters - the Scorer description to send to the server

Returns:

true if we seem to have sent the data successfully to the server

getTargetPercentCPU

int getTargetPercentCPU()

Get current target CPU load percentage in range ]1,100[.

setTargetPercentCPU

void setTargetPercentCPU(int pc)

Set current target CPU load percentage in range ]1,100[. An out-of-range value is coerced into range.

We also adjust the CPU chunk size for better scheduling and CPU behaviour at extremes.

Parameters:

pc - target percent CPU time in the range 1 to 100.

getGeneration

int getGeneration()

Get generation number; strictly positive.

getPopulationSize

int getPopulationSize()

Allow polling for population size; non-negative.

getCalibrationSetSize

int getCalibrationSetSize()

Get size of current calibration set, or zero if none.

getScorersReported

final int getScorersReported()

Get number of Scorers reported back home; never negative.

getLastSAC

ScoreAndConf getLastSAC()

Get score/confidence of last Scorer reported; never null.

getGenTimeRemaining

int getGenTimeRemaining()

Get time remaining for this generation; reset if a new/best Scorer is found.

doWork

void doWork()

Simple core worker routine, usually runs until JVM terminates. Creates a communication tunnel back home, then runs whatever work needs doing.

Will quit immediately if it cannot "call home" when it starts up. Thereafter it will retry to overcome errors as necessary.

Not thread-safe (ie only one thread should call this at once for this instance).

Package-visible to be exposed only to this package.

shutdown

public void shutdown()

Try to shut down quickly and gracefully and with minimal loss of work. We try to flush any pending results back to the server.