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From Ted Dunning <ted.dunn...@gmail.com>
Subject Re: Hadoop should target C++/LLVM not Java
Date Wed, 13 May 2009 17:42:51 GMT
As an example and reminder for those of us who haven't worked in C++ for a
while, take this bug from hypertable:

    Defect     Accepted     Medium     ----     nuggetwheat
Rangeserver crashes if system clock is forwarded.

The rangeserver *crashes* if you change the clock?!?!

On Wed, May 13, 2009 at 10:40 AM, Ted Dunning <ted.dunning@gmail.com> wrote:

>
> The conclusion as stated was "It is just almost always worthwhile...".  I
> think we both agree that anymore that the conclusion by be "There still
> exist a few instances where it is worthwhile..".  The question is when.
>
> My take on the issue is that Hadoop would be completely moribund if it had
> been developed in C++ because it would have been non-portable and would now
> be stuck in a morass of segment faults.  Not to mention that using C++ would
> have meant that Hadoop would have had to make do without Doug C.  Java's
> virtues in terms of safety are particularly valuable in a community
> project.  Conversely, C++'s defects are particularly egregious and dangerous
> in the same setting.
>
>
> On Wed, May 13, 2009 at 8:49 AM, Sean Owen <srowen@gmail.com> wrote:
>
>> Er, isn't it right fact, conclusion that was really right then and
>> remains a little right now? it is the same reason indeed.
>>
>> On Wed, May 13, 2009 at 4:01 PM, Ted Dunning <ted.dunning@gmail.com>
>> wrote:
>> > Right fact (google based their map-reduce on c++), wrong conclusion.
>> >
>> > A simpler motivating factor was simply when Google did it.  In 2001 or
>> so,
>> > Java was definitely much less competitive.
>> >
>> > On Wed, May 13, 2009 at 6:18 AM, Sean Owen <srowen@gmail.com> wrote:
>> >
>> >> For reference, of course, Google operates at such a scale that they
>> >> use a C++-based MapReduce framework. It is just almost always
>> >> worthwhile to spend the time to beat Java performance.
>> >>
>> >
>>
>
>
>
> --
> Ted Dunning, CTO
> DeepDyve
> =

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