Comment 1 John Arthorne 2006-01-17 16:57:28 EST

Created attachment 33174 [details]
patch to use nio channel copy

Comment 2 John Arthorne 2006-01-19 11:16:47 EST

Results were disappointing.  Using FileChannel#transferTo, it was about the same speed on Windows, and about 4% slower on Linux GTK (although the same benchmark was 20x faster on my dual 3GH Linux box to start with).

Comment 3 John Arthorne 2006-01-24 10:16:25 EST

Created attachment 33512 [details]
Latest Channel copy patch

Comment 4 John Arthorne 2006-01-24 10:19:01 EST

Created attachment 33513 [details]
Latest Channel copy patch

Oops, I attached that before the patch wizard had finished, so it was the old patch again.  This is the latest.

Comment 5 John Arthorne 2006-01-24 11:12:49 EST

I have tested the following platform/VMs:

Windows Sun 1.4.2
Windows IBM 1.4.2
Windows Sun 1.5.0_05
Linux Sun 1.4.2
Linux IBM 1.4.2

On all platforms except Linux IBM, the performance is the same within the margin of error, on Linux IBM it is 4% slower with a 2% margin of error.  So, I am going to release this because the code is much cleaner and simpler, and future VM versions have much more potential to optimize FileChannel#transferTo than a simple FileInputStream/FileOutputStream copy using a buffer in the Java heap.

Comment 6 John Arthorne 2006-01-24 11:25:27 EST

I have released the latest patch.

Comment 7 John Arthorne 2006-05-03 11:23:31 EDT

Reopening - this change was reverted due to test failures.

Comment 8 John Arthorne 2006-05-03 11:23:43 EDT

Closing.