Re: [ferret_users] Limit of memory allocation

[Jaison Kurian <jaison@xxxxxxxxxxxxxxxxxx>]

Hi Hiroyuki,
              This is a discussion rather than an answer to your
question.

   Often the Ferret memory requests will not go beyond a certain value 
and the possible reasons can be the machine's memory limitations, 
already running applications (other than Ferret) which access 
considerable share of the available memory etc.

  In these sort of situations, I used to do the job in multiple 
steps, within a REPEAT loop. The explanation is that, Ferret needs
very big memory access only when it does some calculation/regridding
over the entire dataset and writes out the result in a single stretch.
In this case, I used to do the writing part inside a repeat loop.
Suppose we are trying to display the result of calculation/regridding,
we often need to set one/two dimentions to fixed points and in this 
case Ferret does not require such a large memory access. But if this
display step includes some sort of calculation over the entire dataset
again (eg. average over the entire time period), fixing one/two 
dimensions may not help. However, you can write out the results from
first step and then use this intermediate file for displaying the data.

  In summary, if you can exactly describe what you are trying to do,
I can offer a better solution. Please let me know if you have any 
questions on the above discussion.

Regards,

Jaison


On Wed, 18 Apr 2007, Hiroyuki Tomita wrote:

> Hi ferret users:
> 
> I have a question about "SET MEMORY" command.
> 
> Although physical memory of 5 GB have installed in my Mac,
> the allocation of memory in Ferret is limited to about 512 M words (2  
> GB)
> by SET MEMORY command.
> 
> I need to allocate larger memory (about 900 M words) in my jnl script.
> How can I solve this problem?
> 
> The following is my ferret environment.
> Ferret V5.70
> Mac OS X Tiger (10.4.9)
> MacPro with 5GB memory
> 
> Best regards,
> 
> Hiroyuki
> 
> 
> 
> 
>