Chunks vs Arrays - surprising benchmarking results

[Richard Gaskin]

Trevor DeVore wrote:

> On Aug 5, 2009, at 3:05 PM, Richard Gaskin wrote:
> 
>> Any thoughts on how I might optimize the array functions?  Did I  
>> just overlook something obvious which would make them run faster?
> 
> Richard,
> 
> The main slowdown in your test for GetFromMainArray seems to be in  
> transferring the data from the custom property to tDataA. This is  
> consistent with my findings when implementing persistent data storage  
> in the data grid.
> 
> I changed the code a bit so that the field contents and uData custom  
> prop array were put into script locals outside of the timers. Here is  
> what I got:
> 
> GetFromList: 30
> GetFromSubArray: 244
> GetFromMainArray: 27
> All results the same?: true
> 
> So if your data is already in a script local then arrays seem to be  
> faster.

Excellent sleuthing, Trevor.   Confirmed:  with that change I'm getting 
the same results.  Who would have thought there could be so much 
overhead moving a custom property array into a variable array?

Unfortunately for my case, this data is only one of several tables 
stored in user documents.  I could move all the data out of the stack 
file I'm using for the document into a global when the document is 
opened, and could even use a master array within the global to keep the 
data from different open documents separate, but that adds another layer 
of management and the increase in data size for a speed gain of 0.03ms 
per iteration.

I had hoped that I might be able to get around the need to copy the data 
out of the properties by using array notation directly on those 
properties, but alas it doesn't seem the property array syntax is yet 
parallel with variable array syntax as it used to be before we got 
multi-dimensional arrays.

I'll think this over, but so far the two methods are so close in 
performance that I'm inclined to stick with what's in place with chunk 
expressions for now.

Thanks again for finding the bottleneck in the data loading.  That's 
valuable info.

--
  Richard Gaskin
  Fourth World
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