[java-dev] Re: Performance differences between Windows & Mac OS Jit/Java

On Jan 23, 2008, at 3:06 AM, Peter Castine wrote:

>
> Some examination last night turned up another bottleneck... I was  
> using the very convenient JitterMatrix.getcell2dInt(), but the  
> copyMatrixToArray() methods appear to be a lot more efficient.  
> After thinking about it a bit I'm feeling a little stoopid for  
> having chosen the cell-by-cell approach at all, but just based on  
> the docs it's not immediately obvious that the one approach would  
> be more efficient than the other.

Cell process and vec process examples are pretty clear. Yes. Never do  
cell by cell access if it can be avoided. This results in a boundary  
crossing (Java->C) for each cell, rather than once per row, or per  
matrix. Sounds like context switches are much slower on OS X than  
Windows, though on any platform, they are relatively expensive  
operations.

-Joshua