wvlet.log.io

package wvlet.log.io

Members list

Type members

Classlikes

object IOUtil

Attributes

Supertypes
class Object
trait Matchable
class Any
Self type
IOUtil.type
object Resource

Resource file manager.

Resource file manager.

Attributes

Supertypes
class Object
trait Matchable
class Any
Self type
Resource.type

Extend this trait to add support your class for reading resources

Extend this trait to add support your class for reading resources

Attributes

Supertypes
class Object
trait Matchable
class Any
class StopWatch

Attributes

Supertypes
class Object
trait Matchable
class Any
trait TimeReport extends Ordered[TimeReport]

Summary of the execution times of the code blocks

Summary of the execution times of the code blocks

Attributes

Supertypes
trait Ordered[TimeReport]
trait Comparable[TimeReport]
class Object
trait Matchable
class Any
trait Timer extends Serializable

Timer trait measures the performance of code blocks. Extend this trait and wrap the code to measure with time(code_name){ ... }:

Timer trait measures the performance of code blocks. Extend this trait and wrap the code to measure with time(code_name){ ... }:

class A extends Timer {
 val t : TimeReport = time("performance test") {
   // write any code here
   block("A") {
     // code A
   }
   block("B") {
     // code B
   }
 }
 // report elapsed time of A, B and the total running time
 println(t)

 t("A").average // the average of running time of code block "A" (min and max are also available)
}

Timer can take the average of repetitive executions:

class Rep extends Timer {

 // Repeat 10 times the evaluation of the whole block
 val t = time("repetitive evaluation", repeat=10) {
     // This part will be executed 1000 x 10 times
     block("A", repeat=1000) {
       // code A
     }

     // This part will be executed 1000 x 10 times
     block("B", repeat=1000) {
       // code B
     }
 }

 println(t)

 // Which code is faster?
 if(t("A") <= t("B"))
     println("A is faster")
 else
     println("B is faster")
}

When measuring Scala (Java) code performances, you should take the average of execution times and reorder the code block execution orders, because JVM has JIT compiler, which optimizes the code at runtime. And also cache usage and the running state of the garbage core (GC) affects the code performance. By repeating the executions of the entire or individual blocks with the repeat option, you can avoid such pitfalls of benchmarking.

Attributes

Supertypes
trait Serializable
class Object
trait Matchable
class Any