net.openhft.chronicle.queue

Enum RollCycles

java.lang.Object

java.lang.Enum<RollCycles>

net.openhft.chronicle.queue.RollCycles

All Implemented Interfaces:

Serializable, Comparable<RollCycles>, RollCycle

public enum RollCycles
extends Enum<RollCycles>
implements RollCycle

Roll cycles to use with the queue. Sparse indexing roll cycles are useful for improving write performance but they slightly slow random access performance (with no effect for sequential reads)

Enum Constant Summary

Enum Constants

Enum Constant and Description
DAILY 4,294,967,295 entries per day, indexing every 64th entry, leave as 8K and 64 for historical reasons.
FAST_DAILY 4,294,967,295 entries per day, indexing every 256th entry, leave as 4K and 256 for historical reasons.
FAST_HOURLY 4,294,967,295 entries per hour, indexing every 256th entry, leave as 4K and 256 for historical reasons.
FIVE_MINUTELY 1,073,741,824 entries per 5 minutes, indexing every 256th entry
FOUR_HOURLY 4,294,967,295 entries per four hours, indexing every 256th entry
HALF_HOURLY 1,073,741,824 entries per half hour, indexing every 256th entry
HOURLY 268,435,456 entries per hour, indexing every 16th entry, leave as 4K and 16 for historical reasons.
HUGE_DAILY 281,474,976,710,655 entries per day with sparse indexing (every 1024th entry)
HUGE_DAILY_XSPARSE 281,474,976,710,655 entries per day with super-sparse indexing (every (2^20)th entry)
LARGE_DAILY 137,438,953,471 entries per day, indexing every 128th entry
LARGE_HOURLY 4,294,967,295 entries per hour, indexing every 64th entry
LARGE_HOURLY_SPARSE 17,179,869,183 entries per hour with sparse indexing (every 1024th entry)
LARGE_HOURLY_XSPARSE 4,398,046,511,103 entries per hour with super-sparse indexing (every (2^20)th entry)
MINUTELY 67,108,864 entries per minute, indexing every 16th entry
SIX_HOURLY 4,294,967,295 entries per six hours, indexing every 256th entry
SMALL_DAILY 536,870,912 entries per day, indexing every 8th entry
TEN_MINUTELY 1,073,741,824 entries per 10 minutes, indexing every 256th entry
TEST_DAILY 64 entries per day - Only good for testing
TEST_HOURLY 1,024 entries per hour - Only good for testing
TEST_SECONDLY 4,294,967,295 entries - Only good for testing
TEST2_DAILY 512 entries per day - Only good for testing
TEST4_DAILY 4,096 entries per day - Only good for testing
TEST4_SECONDLY 4,096 entries - Only good for testing
TEST8_DAILY 131,072 entries per day - Only good for testing
TWENTY_MINUTELY 1,073,741,824 entries per 20 minutes, indexing every 256th entry
TWO_HOURLY 4,294,967,295 entries per 2 hours, indexing every 256th entry
XLARGE_DAILY 4,398,046,511,103 entries per day, indexing every 256th entry

Field Summary

Fields

Modifier and Type	Field and Description
static RollCycles	DEFAULT

Method Summary

Modifier and Type	Method and Description
static Iterable<RollCycles>	all()
int	current(@NotNull net.openhft.chronicle.core.time.TimeProvider time, long epoch)
int	defaultIndexCount()
int	defaultIndexSpacing() Returns the space between excerpts that are explicitly indexed.
String	format() Returns the format that is to be applied when file names are calculated for a new roll cycle.
int	lengthInMillis() Returns the length in milliseconds (i.e.
long	maxMessagesPerCycle()
static long	maxMessagesPerCycle(long sequenceMask, int indexCount, int indexSpacing)
int	toCycle(long index) Returns the cycle for the given index.
long	toIndex(int cycle, long sequenceNumber) Returns the index for the given cycle and sequenceNumber.
long	toSequenceNumber(long index) Returns the sequence number for the given index.
static RollCycles	valueOf(String name) Returns the enum constant of this type with the specified name.
static RollCycles[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface net.openhft.chronicle.queue.RollCycle

length

Enum Constant Detail

FIVE_MINUTELY

public static final RollCycles FIVE_MINUTELY

1,073,741,824 entries per 5 minutes, indexing every 256th entry

TEN_MINUTELY

public static final RollCycles TEN_MINUTELY

1,073,741,824 entries per 10 minutes, indexing every 256th entry

TWENTY_MINUTELY

public static final RollCycles TWENTY_MINUTELY

1,073,741,824 entries per 20 minutes, indexing every 256th entry

HALF_HOURLY

public static final RollCycles HALF_HOURLY

1,073,741,824 entries per half hour, indexing every 256th entry

FAST_HOURLY

public static final RollCycles FAST_HOURLY

4,294,967,295 entries per hour, indexing every 256th entry, leave as 4K and 256 for historical reasons.

TWO_HOURLY

public static final RollCycles TWO_HOURLY

4,294,967,295 entries per 2 hours, indexing every 256th entry

FOUR_HOURLY

public static final RollCycles FOUR_HOURLY

4,294,967,295 entries per four hours, indexing every 256th entry

SIX_HOURLY

public static final RollCycles SIX_HOURLY

4,294,967,295 entries per six hours, indexing every 256th entry

FAST_DAILY

public static final RollCycles FAST_DAILY

4,294,967,295 entries per day, indexing every 256th entry, leave as 4K and 256 for historical reasons.

MINUTELY

public static final RollCycles MINUTELY

67,108,864 entries per minute, indexing every 16th entry

HOURLY

public static final RollCycles HOURLY

268,435,456 entries per hour, indexing every 16th entry, leave as 4K and 16 for historical reasons.

DAILY

public static final RollCycles DAILY

4,294,967,295 entries per day, indexing every 64th entry, leave as 8K and 64 for historical reasons.

LARGE_HOURLY

public static final RollCycles LARGE_HOURLY

4,294,967,295 entries per hour, indexing every 64th entry

LARGE_DAILY

public static final RollCycles LARGE_DAILY

137,438,953,471 entries per day, indexing every 128th entry

XLARGE_DAILY

public static final RollCycles XLARGE_DAILY

4,398,046,511,103 entries per day, indexing every 256th entry

HUGE_DAILY

public static final RollCycles HUGE_DAILY

281,474,976,710,655 entries per day with sparse indexing (every 1024th entry)

SMALL_DAILY

public static final RollCycles SMALL_DAILY

536,870,912 entries per day, indexing every 8th entry

LARGE_HOURLY_SPARSE

public static final RollCycles LARGE_HOURLY_SPARSE

17,179,869,183 entries per hour with sparse indexing (every 1024th entry)

LARGE_HOURLY_XSPARSE

public static final RollCycles LARGE_HOURLY_XSPARSE

4,398,046,511,103 entries per hour with super-sparse indexing (every (2^20)th entry)

HUGE_DAILY_XSPARSE

public static final RollCycles HUGE_DAILY_XSPARSE

281,474,976,710,655 entries per day with super-sparse indexing (every (2^20)th entry)

TEST_SECONDLY

public static final RollCycles TEST_SECONDLY

4,294,967,295 entries - Only good for testing

TEST4_SECONDLY

public static final RollCycles TEST4_SECONDLY

4,096 entries - Only good for testing

TEST_HOURLY

public static final RollCycles TEST_HOURLY

1,024 entries per hour - Only good for testing

TEST_DAILY

public static final RollCycles TEST_DAILY

64 entries per day - Only good for testing

TEST2_DAILY

public static final RollCycles TEST2_DAILY

512 entries per day - Only good for testing

TEST4_DAILY

public static final RollCycles TEST4_DAILY

4,096 entries per day - Only good for testing

TEST8_DAILY

public static final RollCycles TEST8_DAILY

131,072 entries per day - Only good for testing

Field Detail

DEFAULT

public static final RollCycles DEFAULT

Method Detail

values

public static RollCycles[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (RollCycles c : RollCycles.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static RollCycles valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

maxMessagesPerCycle

public long maxMessagesPerCycle()

Specified by:

maxMessagesPerCycle in interface RollCycle

Returns:

the maximum number of messages per cycle

all

public static Iterable<RollCycles> all()

format

public String format()

Description copied from interface: RollCycle

Returns the format that is to be applied when file names are calculated for a new roll cycle.

For example, the following formats can be returned:

• "yyyyMMdd-HHmm" (MINUTELY)
• "yyyyMMdd" (DAILY)

Specified by:

format in interface RollCycle

Returns:

the format that is to be applied when file names are calculated for a new roll cycle

lengthInMillis

public int lengthInMillis()

Description copied from interface: RollCycle

Returns the length in milliseconds (i.e. the maximum duration) for a roll cycle.

For example, the following lengths can be returned:

• 60 * 1,000 = 60,000 (MINUTELY)
• 24 * 60 * 60 * 1,000 = 86,400,000 (DAILY)

Specified by:

lengthInMillis in interface RollCycle

Returns:

the length in milliseconds (i.e. the maximum duration) for a roll cycle

defaultIndexCount

public int defaultIndexCount()

Specified by:

defaultIndexCount in interface RollCycle

Returns:

this is the size of each index array, note: indexCount^2 is the maximum number of index queue entries.

defaultIndexSpacing

public int defaultIndexSpacing()

Description copied from interface: RollCycle

Returns the space between excerpts that are explicitly indexed.

A higher number means higher sequential write performance but slower random access read. The sequential read performance is not affected by this property.

For example, the following default index spacing can be returned:

• 16 (MINUTELY)
• 64 (DAILY)

Specified by:

defaultIndexSpacing in interface RollCycle

Returns:

the space between excerpts that are explicitly indexed

current

public int current(@NotNull
                   @NotNull net.openhft.chronicle.core.time.TimeProvider time,
                   long epoch)

Specified by:

current in interface RollCycle

epoch - and EPOCH offset, to all the user to define their own epoch

Returns:

the cycle

toIndex

public long toIndex(int cycle,
                    long sequenceNumber)

Description copied from interface: RollCycle

Returns the index for the given cycle and sequenceNumber.

An index is comprised of both a cycle and a sequence number but the way the index is composed of said properties may vary.

Specified by:

toIndex in interface RollCycle

Parameters:

cycle - to be composed into an index

sequenceNumber - to be composed into an index

Returns:

the index for the given cycle and sequenceNumber

toSequenceNumber

public long toSequenceNumber(long index)

Description copied from interface: RollCycle

Returns the sequence number for the given index.

An index is comprised of both a cycle and a sequence number but the way the index is composed of said properties may vary. This method decomposes the provided index and extracts the sequence number.

Specified by:

toSequenceNumber in interface RollCycle

Parameters:

index - to use when extracting the sequence number

Returns:

the sequence number for the given index

toCycle

public int toCycle(long index)

Description copied from interface: RollCycle

Returns the cycle for the given index.

An index is comprised of both a cycle and a sequence number but the way the index is composed of said properties may vary. This method decomposes the provided index and extracts the cycle.

Specified by:

toCycle in interface RollCycle

Parameters:

index - to use when extracting the cycle

Returns:

the sequence number for the given index

maxMessagesPerCycle

public static long maxMessagesPerCycle(long sequenceMask,
                                       int indexCount,
                                       int indexSpacing)