Miscellaneous improvements to "jar".

[Xueming Shen]

Ulf Zibis wrote:
> Am 26.06.2009 17:47, Xueming Shen schrieb:
>> Ulf,
>>
>> 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).
>
> Often those bits are just cached in memory from OS side, maybe also 
> big chunks of rt.jar and charsets.jar after VM is launched.
> Another 2 cents!
>
> -Ulf
>
>
>
Our performance team works on both warm start and cold start, the terms 
we use for the them:-)