com.netflix.spectator.api

Interface Timer

All Superinterfaces:

Meter

All Known Implementing Classes:

AbstractTimer, BucketTimer, PercentileTimer

public interface Timer
extends Meter

Timer intended to track a large number of short running events. Example would be something like an http request. Though "short running" is a bit subjective the assumption is that it should be under a minute. The precise set of information maintained by the timer depends on the implementation. Most should try to provide a consistent implementation of count() and totalTime(), but some implementations may not. In particular, the implementation from NoopRegistry will always return 0.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	Timer.BatchUpdater See batchUpdater(int).

Method Summary

Modifier and Type	Method and Description
default Timer.BatchUpdater	batchUpdater(int batchSize) Returns a helper that can be used to more efficiently update the timer within a single thread.
long	count() The number of times that record has been called since this timer was last reset.
<T> T	record(Callable<T> f) Executes the callable `f` and records the time taken.
default void	record(Duration amount) Updates the statistics kept by the timer with the specified amount.
default void	record(Duration[] amounts, int n) Updates the statistics kept by the timer with the specified amounts.
default void	record(long[] amounts, int n, TimeUnit unit) Updates the statistics kept by the timer with the specified amounts.
void	record(long amount, TimeUnit unit) Updates the statistics kept by the timer with the specified amount.
void	record(Runnable f) Executes the runnable `f` and records the time taken.
long	totalTime() The total time in nanoseconds of all recorded events since this timer was last reset.

Methods inherited from interface com.netflix.spectator.api.Meter

hasExpired, id, measure

Method Detail

record

void record(long amount,
            TimeUnit unit)

Updates the statistics kept by the timer with the specified amount.

Parameters:

amount - Duration of a single event being measured by this timer. If the amount is less than 0 the value will be dropped.

unit - Time unit for the amount being recorded.

record

default void record(Duration amount)

Updates the statistics kept by the timer with the specified amount.

Parameters:

amount - Duration of a single event being measured by this timer.

record

default void record(long[] amounts,
                    int n,
                    TimeUnit unit)

Updates the statistics kept by the timer with the specified amounts. Behaves as if `record()` was called in a loop, but may be faster in some cases.

Parameters:

amounts - Duration of events being measured by this timer. If the amount is less than 0 for a value, the value will be dropped.

n - The number of elements to write from the amounts array (starting from 0). If n is <= 0 no entries will be recorded. If n is greater than amounts.length, all amounts will be recorded.

unit - Time unit for the amounts being recorded.

See Also:

record(long, TimeUnit)

record

default void record(Duration[] amounts,
                    int n)

Updates the statistics kept by the timer with the specified amounts. Behaves as if `record()` was called in a loop, but may be faster in some cases.

Parameters:

amounts - Duration of events being measured by this timer. If the amount is less than 0 for a value, the value will be dropped.

n - The number of elements to write from the amounts array (starting from 0). If n is <= 0 no entries will be recorded. If n is greater than amounts.length, all amounts will be recorded.

See Also:

record(Duration)

record

<T> T record(Callable<T> f)
      throws Exception

Executes the callable `f` and records the time taken.

Parameters:

f - Function to execute and measure the execution time.

Returns:

The return value of `f`.

Throws:

Exception

record

void record(Runnable f)

Executes the runnable `f` and records the time taken.

Parameters:

f - Function to execute and measure the execution time.

count

long count()

The number of times that record has been called since this timer was last reset. How often a timer is reset depends on the underlying registry implementation.

totalTime

long totalTime()

The total time in nanoseconds of all recorded events since this timer was last reset. How often a timer is reset depends on the underlying registry implementation.

batchUpdater

default Timer.BatchUpdater batchUpdater(int batchSize)

Returns a helper that can be used to more efficiently update the timer within a single thread. For example, if you need to update a meter within a loop where the rest of the loop body is fairly cheap, the instrumentation code may add considerable overhead if done in the loop body. A batched updater can offset a fair amount of that cost, but the updates may be delayed a bit in reaching the meter. The updates will only be seen after the updater is explicitly flushed. The caller should ensure that the updater is closed after using to guarantee any resources associated with it are cleaned up. In some cases failure to close the updater could result in a memory leak.

Parameters:

batchSize - Number of updates to batch before forcing a flush to the meter.

Returns:

Batch updater implementation for this meter.