Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.lang.ruby > #4694

Re: Need for speed - array operations

From Joel VanderWerf <joelvanderwerf@gmail.com>
Newsgroups comp.lang.ruby
Subject Re: Need for speed - array operations
Date 2011-05-17 16:23 -0500
Organization Service de news de lacave.net
Message-ID <4DD2E763.4010600@gmail.com> (permalink)
References <2c5b9893b3d3fa487c6b9737df7c8df2@ruby-forum.com> <e2c62ac1401e32aa2201191e88271de7@ruby-forum.com>

Show all headers | View raw


On 05/17/2011 01:26 PM, Pirogov Eugene wrote:
> I'm experience the loss of speed in NArrays. Did you guys tried benching
> a simple access to an element in NArray?
>
> My benches show dramatical slowdown comparing to a Ruby built-in Array.
> I already filled an issue here:
> https://github.com/masa16/narray/issues/8.
>

It's too simple a benchmark to demonstrate the efficiency of narray. 
What it's measuring is access time from ruby. For the first two cases, 
the number in the ruby array is a fixnum (shifted by one bit and or-ed 
with 0x01) that can simply be returned with no modification, as a 32 or 
64 bit VALUE (ruby's basic data type). In the third case, the number is 
stored as an 8 bit signed int, which has to be converted to VALUE by 
sign extending, shifting, and or-ing.

As soon as you start measuring operations whose inputs and outputs are 
both NArrays (especially large ones), you'll see the speed...

Back to comp.lang.ruby | Previous | NextPrevious in thread | Find similar | Unroll thread


Thread

Need for speed - array operations Chris Lervag <chris.lervag@gmail.com> - 2011-04-29 03:54 -0500
  Re: Need for speed - array operations Ralf Mueller <ralf.mueller@zmaw.de> - 2011-04-29 06:05 -0500
    Re: Need for speed - array operations Robert Klemme <shortcutter@googlemail.com> - 2011-04-29 06:23 -0500
  Re: Need for speed - array operations Chris Lervag <chris.lervag@gmail.com> - 2011-04-29 09:05 -0500
  Re: Need for speed - array operations Chris Lervag <chris.lervag@gmail.com> - 2011-04-29 16:45 -0500
  Re: Need for speed - array operations Pirogov Eugene <iamexile@gmail.com> - 2011-05-17 15:26 -0500
    Re: Need for speed - array operations Joel VanderWerf <joelvanderwerf@gmail.com> - 2011-05-17 16:23 -0500

csiph-web