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Instance Padding

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 Hi All ,

Can any one suggest me how should i specify instance padding  i am using following commands but by executing these , specified padding is not appllied for the instance after placement.

specifyInstPad <instancename> 2

placeDesign.

  • By "not applied" do you mean you suspect the directive is being silently disregarded by the placer? Or the placer isn't honoring your request as judged by visual inspection?

    If you suspect it's being silently disregarded check the value with "reportInstPad" to make sure the padding you requested is still there.

    If you suspect the placer isn't honoring your constraints, consider a few things:

    • The value is specified in placement site units
    • The padding isn't guaranteed to occur on a specific side of a given instance
    • You can see what the unit size looks like visually compared to the cells by turning on placemen site visibility: All Colors->View Only->Row Site Pattern 

    I suspect that the value of "2" is just really small. Try a larger value, like one which equates to 50-100% the size of the instance you want padded.
     
    Hope this helps,
    Bob 

     

  • Thanks BobD for your valid information.

    reportInstPad is still giving the instances for which i applied padding , but after placement i am not able to visually observing the padding in any side of the instance ,  i tried with larger value of padding also but visually i am not able to see the padding. what might be the reason?

     

  • Hmm. I'd suspect one of 2 things. Either the overall density is so high that the padding can't be honored. Or that some other placement setting is taking precedence over the instance padding. If the overall density is moderate (<95%) I'd try an experiment where I cleared out all non-default placement settings (setPlaceMode -reset), applied the instance padding, and ran a simple placeDesign. Let us know what you find! Sounds like an interesting puzzler.

    PS You're always free to file a service request and if you can provide a testcase we'll be able to pin it down. Thanks for using the forums!

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