From: Tanaka Akira <akr@...>
Date: 2013-07-21T16:55:58+09:00
Subject: [ruby-core:56101] Re: [ruby-trunk - Feature #8658][Open] Process.clock_gettime

2013/7/21 "Martin J. D�rst" <duerst@it.aoyama.ac.jp>:
>
> On 2013/07/19 21:32, akr (Akira Tanaka) wrote:
>
>> On LP64 systems, Fixnum can represent 2**62-1.
>> So (2**62-1)/(365.25*24*60*60*1e9)=146.1 years are representable
>> without object allocation.
>>
>> On ILP32 and LLP64 systems, Fixnum can represent 2**30-1.
>> So (2**30-1)/1e9=1.07 seconds are representable
>> without object allocation.
>> This means Bignum allocations are mostly required except
>> the origin is very recent.
>
>
> Don't your calculations ignore the fact that Fixnums are signed? Or do you
> have a way to use negative amounts of nanoseconds, too?

% ./ruby -ve 'p (2**62-1).class, (2**62).class'
ruby 2.1.0dev (2013-07-21 trunk 42095) [x86_64-linux]
Fixnum
Bignum

% ./ruby -ve 'p (2**30-1).class, (2**30).class'
ruby 2.1.0dev (2013-07-21 trunk 42095) [i686-linux]
Fixnum
Bignum

What's the problem?
-- 
Tanaka Akira