Revision: 269
http://assorted.svn.sourceforge.net/assorted/?rev=269&view=rev
Author: yangzhang
Date: 2008-01-20 23:22:45 -0800 (Sun, 20 Jan 2008)
Log Message:
-----------
added timebench
Added Paths:
-----------
sandbox/trunk/src/java/TimeBench.java
Added: sandbox/trunk/src/java/TimeBench.java
===================================================================
--- sandbox/trunk/src/java/TimeBench.java (rev 0)
+++ sandbox/trunk/src/java/TimeBench.java 2008-01-21 07:22:45 UTC (rev 269)
@@ -0,0 +1,50 @@
+public class TimeBench {
+
+ public static void main(String[] args) {
+ // On my dual-core Intel machine, millis is *faster* than nano, despite the
+ // fact that FreeNode folk told me nano was more accurate (perhaps it is
+ // once you get to that granularity, but the cost of invocation is twice as
+ // high):
+ //
+ // $ for i in {1..10}; do java TimeBench; done
+ // 213
+ // 416283169
+ // 210
+ // 427611823
+ // 211
+ // 425782976
+ // 211
+ // 416913721
+ // 213
+ // 419326076
+ // 209
+ // 415857948
+ // 209
+ // 415659440
+ // 210
+ // 410968289
+ // 212
+ // 421450138
+ // 216
+ // 417043555
+ //
+ // Furthermore, I verified using strace, that none of these produces
+ // syscalls.
+
+ {
+ long t = System.currentTimeMillis(), t0 = System.currentTimeMillis();
+ for (int i = 0; i < 1000000; i++)
+ t = System.currentTimeMillis();
+ System.out.println(t - t0);
+ }
+
+ {
+ long t = System.nanoTime(), t0 = System.nanoTime();
+ for (int i = 0; i < 1000000; i++)
+ t = System.nanoTime();
+ System.out.println(t - t0);
+ }
+
+ }
+
+}
This was sent by the SourceForge.net collaborative development platform, the world's largest Open Source development site.
|
