com.neeve.stats

Class StatsLatencyWriter

java.lang.Object

com.neeve.stats.StatsLatencyWriter

public final class StatsLatencyWriter
extends Object

Utility class containing methods to write performance latencies to a file

This class MAY be used by end users, however it is not supported.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	StatsLatencyWriter.Stats

Constructor Summary

Constructors

Constructor and Description
StatsLatencyWriter(String name, String filename, boolean printIntervalStats) Construct a latency writer Invokes this(filename, true, printIntervalStats, false)
StatsLatencyWriter(String name, String filename, boolean printHeader, boolean printIntervalStats, boolean printStatsInNanos) Construct a latency writer

Method Summary

Modifier and Type	Method and Description
void	close() Close a latency writer Invokes close(true)
void	close(boolean finish) Close a latency writer
void	close(int warmupCount, StatsLatencyWriter.Stats stats) Close a latency writer
static void	closeNative(long lw, int finalCount, boolean finish) Close a native latency writer
static long	createNative(String name, String filename, boolean printHeader, boolean printIntervalStats, boolean printStatsInNanos) Create a new native latency writer
static void	destroyNative(long lw) Destroy a native latency writer
void	finish() Print finish line
static boolean	isNativeEnabled() Get whether native is enabled and in use
static void	processNative(long lw, long latencies, long itotal, long total, int icount, int count, int max) Process a set of collected latencies
void	start(int rate, int count) Start a latency writer
static void	startNative(long lw) Start a native latency writer
void	stop() Stop a latency writer
boolean	write(int val) Write a latency data point

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

StatsLatencyWriter

public StatsLatencyWriter(String name,
                          String filename,
                          boolean printHeader,
                          boolean printIntervalStats,
                          boolean printStatsInNanos)
                   throws Exception

Construct a latency writer

Parameters:

name - The name of the stats series

filename - The file to write the latencies to. Can be null if latencies are not to be written

printHeader - Whether the latencies header should be printed. This should normally be true unless multiple latency writers are being employed and only one of them should print the header

printIntervalStats - Whether to print stats on each interval that the stats are written to the file. Otherwise, only aggregate stats fot the full run are printed at the end of the run

printStatsInNanos - If true, then aggregated stats are printed in nanoseconds. Otherwise, they are printed in microseconds. This parameter does not affect what is written to the latencies file. That is always in nanoseconds i.e. what is supplied to write(int)

Throws:

Exception

StatsLatencyWriter

public StatsLatencyWriter(String name,
                          String filename,
                          boolean printIntervalStats)
                   throws Exception

Construct a latency writer

Invokes this(filename, true, printIntervalStats, false)

Throws:

Exception

Method Detail

isNativeEnabled

public static final boolean isNativeEnabled()

Get whether native is enabled and in use

createNative

public static final long createNative(String name,
                                      String filename,
                                      boolean printHeader,
                                      boolean printIntervalStats,
                                      boolean printStatsInNanos)
                               throws Exception

Create a new native latency writer

Parameters:

filename - The name of the file to which latencies are written

Returns:

A handle to the native latency writer object

Throws:

Exception

startNative

public static final void startNative(long lw)

Start a native latency writer

Parameters:

lw - The name latency writer handle

processNative

public static final void processNative(long lw,
                                       long latencies,
                                       long itotal,
                                       long total,
                                       int icount,
                                       int count,
                                       int max)
                                throws Exception

Process a set of collected latencies

Parameters:

lw - The name latency writer handle

latencies - The native buffer containing the latencies (nanos as consecutive ints)

itotal - The interval latency total (sum of all latencies in this interval)

total - The latency total since start of test (sum of all latencies since start of test)

icount - The number of latencies collected in this interval i.e. the number of latencies in the supplied buffer

count - The total number of latencies collected since the start of the test

max - The max latency since start of test

Throws:

Exception

closeNative

public static final void closeNative(long lw,
                                     int finalCount,
                                     boolean finish)

Close a native latency writer

Parameters:

lw - The name latency writer handle

finalCount - The final count of latencies collected in the test run

finish - Whether the latency writing is finished

destroyNative

public static final void destroyNative(long lw)

Destroy a native latency writer

Parameters:

lw - The name latency writer handle

start

public final void start(int rate,
                        int count)
                 throws Exception

Start a latency writer

Parameters:

rate - The rate at which points will be generated

count - The total number of data points

Throws:

Exception

write

public final boolean write(int val)
                    throws Exception

Write a latency data point

Parameters:

val - The data point, in nanoseconds

Returns:

Returns if the write resulted in the filling up of the latencies buffer and processing/writing of the buffer as configured during start

Throws:

Exception

stop

public final void stop()
                throws Exception

Stop a latency writer

Throws:

Exception

close

public final void close(boolean finish)
                 throws Exception

Close a latency writer

Parameters:

finish - Whether the latency writing is finished

Throws:

Exception

close

public final void close(int warmupCount,
                        StatsLatencyWriter.Stats stats)
                 throws Exception

Close a latency writer

Parameters:

stats - Indicates that latency writing is finished and aggregate stats should be populated in the supplied stats object

Throws:

Exception

close

public final void close()
                 throws Exception

Close a latency writer

Invokes close(true)

Throws:

Exception

finish

public final void finish()

Print finish line