Inventor 2018.1 UseLibXL

[G.Barozzi]

From the Readme file for the 2018.1 Update

http://up.autodesk.com/2018/INVNTOR/Inventor_2018.1_enu.htm:

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Part Modeling

The performance issue loading Thread/Clearance data is resolved. Inventor now reads the Excel spreadsheet for Thread or Clearance data using the Excel libraries, and no longer loads Excel even when Excel is installed on the local machine.

ATTENTION: The environment variable UseLibXL is no longer required, and should be removed from your system as it can prevent Excel from being used for table write operations.

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From the document: What's New for Inventor 2018.1

http://help.autodesk.com/view/INVNTOR/2018/ENU/?guid=GUID-35383566-95AE-4F7A-AEA7-C27CB0ACCE18

Other General Enhancements

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Attention: Previously customers were directed to add the environment variable UseLibXL=1 to resolve the performance issue with loading Thread/Clearance data. The environment variable UseLibXL=1 can be left in place if it is already in use, (or, if it is not already in place, add UseLibXL=1 as an environment variable), as it may continue to improve the performance of iPart/iAssembly related workflows.

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I think that a final and clear word by Autodesk about this subject is needed.

Best Regards

G. Barozzi

[mcgyvr · Accepted solution]

See post #14 and #18 at least for more information..

The basically only half fixed the issues from what I read.

read operations are fixed and don't require the variable.. write operations can benefit from leaving it there..

https://forums.autodesk.com/t5/inventor-forum/general-table-deleting-exiting-text-when-inserting-add...

[Anonymous]

Thanks a lot.

[G.Barozzi]

Thank You.

Best Regards

G. Barozzi

[gilsdorf_e]

As to my experience with UseLibXL:

This breaks iAssembly functionality. All my numbers get some extra digits added in the table, when UseLibXL = 1.
Meaning for example "1000" becomes a "1000.000000" which does not seem bad at a first glance for dimensions. Unfortunately exclude/include component becomes also a "0.000000" or "1.000000" which will kill the iAssembly because Inventor cannot handle it anymore.

[ChrisMitchell01]

The information available is indeed somewhat ambiguous based on when it was published... Things changed recently primarily in later versions of win10 with Excel 2016, when excel based operations took a real performance hit at the API level...

So to try to summarize current position:

If you notice performance issues when working with Excel driven designs then setting the UseLibXL variable will improve things considerably. This shouldn't be necessary anymore for simple things such as reading hole/thread tables as it happens automatically, (as documented for 2018.1) but for larger designs driven by excel there is a definite performance issue.

The use of the UselibXl variable is known to change the accuracy of mantissa as mentioned.

So, if performance is a major concern then set the variable.

If data accuracy is a concern don't set the variable & live with the degraded performance, (or manually activate/deactivate the variable as required).

Not ideal I know; all of this is currently under investigation by the Inventor Dev team, (based on various forum posts here as well as direct product support cases).

Thanks
Chris

[gilsdorf_e]

Hello Chris,

thank you for clarifying. Unfortunately we do not have the choice to set the variable, because as mentioned this will disable include/exclude functionality in iAssemblies.  The performance drop is significant, I measured updating time going from 3 minutes to 11 minutes for a more complex iAssembly.

Could you please point out if this is caused by Excel 2016, Windows 10 or the combination?

Later this day I'm going to make someone take some time measures of the different combination. On my first try it looks like it is more an Excel 2016 problem than a Windows 10 problem.

[xavier_dumont2]

Hello,

Do you know if there is any improvement in R2019.1?

Thanks in advance.

[ChrisMitchell01]

The root cause performance issue which necessitates the use of LibXL in the first place, is currently under investigation for 2019.2; we hope to release that for initial beta testing within about a week.

Thanks

Chris