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Computer Memory Useage

Keith.Dye

I am using Eagle for the first time and trying to route a complex design using 7 routing layers and 3 power layers. When I realised how slow Eagle was on the old CAD computer I purchased a fast quad core computer (i7 with 8 GBytes RAM and Windows 7 64bit). Is there any way I can make Eagle use these resources? Currently it seems to only use one core and up to 2 Gbytes RAM so is constantly using the hard drive.

 

I think the program automatically installed as a 32 bit program using the XP compatible mode.

  • 0

    Hi Keith,

     

    EAGLE is a 32bit application and it can use only one core. In terms of memory EAGLE takes what it needs.

    If EAGLE would need 2 GB of RAM then you should think about the settings for your routing job. I never had a routing job that would require so much memory.

     

    Could you give me more information about your project? How many layers do you use and what is the size of the board? And most important question: What is the routing grid?

     

    Regards,

    Richard

  • 0 in reply to Richard_H

    Hi Richard,

     

    Thank you for the reply. The project board is a double eurocard. I am trying to fit one third of the required components, and so have them bunched fairly tightly - but all on the componet side of the board. There are a mix of 0402/0603 parts, some power drivers with 0.5A and 1A drive capability, two 160 pin rear connectors, one plug in module with 160 pins (hoped to be three modules).

     

    I have tried using 10 layers (7 routing 2 power planes and one layer with different power polygons to support analogue and digital voltages).

     

    The routing grid is 0.05mm. The limiting factor to completing last 5% of routing was not enough space for all the vias (only using through vias at present).

     

    In order to make progress I have spread out the parts and decided to only fit two channels to a card and not three. This has made things faster, and routing with three optimisation passes takes about 12 hours. I have been able to remove two routing layers and so the board is now 8 layer (5 routing, 3power). Checking the resource monitor shows memory at close to 2 MByes, and CPU at only 20%, but still with many disc swaps.

     

    Is a 64 bit version being considered?

  • 0 in reply to Keith.Dye

    Hi Keith,

     

    a routing grid of 0.05 mm is pretty fine. Let me calculate the memory the autorouter will need...........

    The static memory requirement (in bytes) for a board can be calculated as follows:

        number of grid points x number of signal layers x 2

        3200 x 4000 x 5 x 2 = 128,000,000 bytes

    Let's double it for dynamic memory  128,000,000 x 2 = 256,000,000 bytes

    So 256 Mbyte should be enough for the routing process. Don't know why you get lot of disk swapping.....

     

    Concerning your question about a 64bit version. Currently I don't know, but i will forward your request to our development team....


    Regards,

    Richard

  • 0 in reply to Richard_H

    Hi Again,

     

    there is one thing that came into my mind.... Did you draw a board contour in layer 20 Dimension? If not, the autorouter would use the whole drawing area for its calculation which results in much more memory usage.

     

    -Richard