Miscellaneous improvements to "jar".

Ulf Zibis Ulf.Zibis at gmx.de
Fri Jun 26 16:35:27 UTC 2009

Oops, I'm not as fast as you two, writing in english. :-(


Am 26.06.2009 18:04, Martin Buchholz schrieb:
> Removing one layer of BufferedInputStream
> in my change saves one bulk copy per file.
> And reusing the same buffer saves on cache misses
> and GC.  But bulk copy is actually very fast,
> (especially as memory is becoming more like disk),
> so the win is relatively small.
> I would be surprised if you could get more than
> the 10-20% that I've gotten with this change,
> by using direct buffers.
> Martin
> On Fri, Jun 26, 2009 at 08:47, Xueming Shen <Xueming.Shen at sun.com 
> <mailto:Xueming.Shen at sun.com>> wrote:
>     I do have a "prototype implementation" that uses buffer based
>     read/write on Jar/ZipFile, it
>     is not that "much" faster as you would have expected (basically
>     the gain of using direct buffer
>     comes from saving one or two memory copy of the content,  which is
>     very faster, compared to
>     the "real hard" work of moving bits from harddisk to memory).
>     While it's still something
>     worth doing,  but definitely not a high priority for now, yes,
>     it's on the list.
>     Sherman

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