Java performance timing library

Question

I frequent wrap code in a System.nanoTime() pair in order to timing it. Something like:

long start = System.nanoTime();    
methodToBeTimed();
long elapsedTime = System.nanoTime() - start;

There is any good timing library that helps with this problem? Also homegrown code will be accepted.

NB

A profiler is not a solution here, since I want to enforce some time constraints in my unit tests, so I want to timing methods programmatically.

I don't understand what the "problem" is that you are trying to solve. You have one line at the top, and one more line at the bottom to give you elapsed time. And you have one variable to hold it. You could wrap this in a class, or use the Stopwatch class, but you won't really reduce the complexity of the code in any way: you still will need one line at the top, and one line at the bottom. Is it that you want help recording and tracking a large number of such timings? — AgilePro, Jan 22 '13 at 22:40

Mark · Accepted Answer · 2020-01-16T21:36:05.700

10

Ignore this answer as the project is no longer active

I haven't used it but I came across perf4j recently.

edited Jan 16 '20 at 21:36

answered Aug 06 '09 at 08:44

Mark

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@Mark: never heard about it. Thanks very much! – dfa Aug 07 '09 at 10:07
You may even draw graphs with perf4j, with the integrated servlet. It's quite good. – unludo Feb 13 '12 at 08:36
Link is broken :-( – mjaggard Jan 16 '20 at 14:42

score 9 · Answer 2 · answered Aug 06 '09 at 06:12

9

Not a direct answer to your question, but I am also often using this tip to time my code and just wrote the following simple Eclipse -> Surround With template:

long startTime = System.currentTimeMillis();
${line_selection}${cursor}
long totalTime = System.currentTimeMillis() - startTime;
System.out.println("Total time = " + totalTime);
System.out.println();

answered Aug 06 '09 at 06:12

Manuel Selva

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unfortunately I'm a netbeans user -:) – dfa Aug 14 '09 at 06:48

score 8 · Answer 3 · edited Dec 30 '13 at 19:01

8

JUnit 4 got a built-in timing-contraint functionality.

@Test(timeout=X)

should do the trick. X is the maximum number of milliseconds the method is allowed to run.

edited Dec 30 '13 at 19:01

BenMorel

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answered Aug 06 '09 at 08:25

Philipp

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yes, this is a very basilar implementation, essentialy I'm loooking for @Test(timeout=X, repeat=N) then display the average – dfa Aug 06 '09 at 09:04

score 7 · Answer 4 · edited Feb 19 '15 at 04:40

7

there is StopWatch from commons-lang, it also allows you to split timer.

edited Feb 19 '15 at 04:40

user802421

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answered Aug 06 '09 at 06:27

IAdapter

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nice to see it but it only encapsulates System.nanoTime/System.currentTimeMillis calls – dfa Aug 06 '09 at 06:30
its always easier to use than the default version ;) – IAdapter Aug 06 '09 at 07:52

score 4 · Answer 5 · answered Sep 10 '09 at 21:27

4

If you're using Spring you already have nice class called StopWatch in your classpath for this propose.

answered Sep 10 '09 at 21:27

Malax

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score 2 · Answer 6 · edited Dec 07 '11 at 13:49

2

JETM is a good library for doing this. It can also provide with mins, maxs and averages, plus can generate informative graphs.

edited Dec 07 '11 at 13:49

Kai

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answered Dec 07 '11 at 12:54

ahanin

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Looks unmaintained, for anybody interested in this. Runs only on HTTP and JavaDoc is inaccessible. – Maarten Bodewes Oct 09 '22 at 15:23

score 1 · Answer 7 · answered Aug 06 '09 at 06:16

1

Tried JPerf ?

answered Aug 06 '09 at 06:16

techzen

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Use google cache to see usage, Alternatively check the link to xjperf: http://code.google.com/p/xjperf/ – techzen Aug 06 '09 at 06:22
it seems a frontend for iperf, that is "a modern alternative for measuring maximum TCP and UDP bandwidth performance". It is right? – dfa Aug 06 '09 at 06:25

score 1 · Answer 8 · answered Aug 06 '09 at 06:17

What kind of help are you looking for with this problem? You have the basics in place. You get the elapsed time in Nanoseconds, accurate to whatever resolution the underlying OS/Hardware is capable of.

Also... and I know you said no profilers... but I have had outstanding experience with YourKit. It provides an API that you can use to control profiling from the outside. Depending on what your exact problem is, this one might be worth having a look at.

score 1 · Answer 9 · answered Sep 25 '14 at 14:06

1

Something new on the market is JMH. It's made under the umbrella of the openjdk project.

answered Sep 25 '14 at 14:06

keiki

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score 1 · Answer 10 · answered Nov 02 '14 at 23:36

1

I've just started using Java Simon (formerly on Google Code), and it seems awesome! A simple set of stopwatches and counters with few dependencies.

answered Nov 02 '14 at 23:36

Garret Wilson

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score 1 · Answer 11 · answered Dec 07 '11 at 13:32

1

Caliper

And in addition to reading the wikis on that site, i recommend reading:

answered Dec 07 '11 at 13:32

nicerobot

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Mike · Answer 12 · 2021-07-25T17:25:58.697

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A simple wrapper for commons-lang StopWatch which take into account multi threading environment, when stop is not invoked leap stat is not counted and 'failed leaps count' incremented (you may not include stop in finally block if the behavior is desired), exposes live statistic via JMX and deliver consolidated serializable result over the network. Example usage:

private PerfStat methodPerf = new PerfStat("method.under.test");
...
public void myMethod() {
    methodPerf.start();
    ...
    long timeNs = methodPerf.stop();
}

dependency

<dependency>
    <groupId>org.droolsassert</groupId>
    <artifactId>da-utils</artifactId>
</dependency>

edited Jul 25 '21 at 17:25

answered May 17 '12 at 12:10

Mike

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I don't think your implementation for `minLapTime` would work, since it is initialized with the lowest possible value: 0. It should probably be initialized with (and reset to) `Long.MAX_VALUE`. – martin May 29 '13 at 09:57

Java performance timing library

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