Performance issue about ExcelDna in Excel 365

[uyuyliu831]

Hi:

We are migrating our Excel Add-in created by ExcelDNA and VB.net from a windows 7 / Excel 2010 32 bit version to a windows 10 / Excel 365 64 bit version.

Everything works fine except that all the modules from the new environment tend to run slower than the old environment. For example, there's one module used to take 35 second to run through under old environment now takes about 1 mins and 5 seconds.

So far I am not able to locate where the slowness comes from.

Checking if anyone has similar experiences on this. Would love to get some ideas.

[augustoproiete]

@uyuyliu831 That's an interesting observation that I haven't experienced myself. Maybe you could start by using a .NET profiler such as dotTrace or ANTS and see if you can find any bottlenecks which might give you some clues about why it's slower (?)

[govert]

There were quite a few performance-related issues in the Excel 2010 -> Excel 2013 time frame, and I think you'll find some COM interop scenarios became much slower.

• https://social.msdn.microsoft.com/Forums/Lync/en-US/7fec88bd-d0ae-42e8-bf3b-efc7934b5cd6/excel-2013-vba-slow-performance-with-specific-commands?forum=exceldev

• https://social.msdn.microsoft.com/Forums/Lync/en-US/6f633bfa-c14d-41d2-a63a-020e0418d5ba/excel-2013-poor-performance-with-rangecopy?forum=exceldev

• https://social.msdn.microsoft.com/Forums/Lync/en-US/56cb00ff-9679-4f15-af5b-7b73e3117d8e/excel-2016-vba-performing-poorly-especially-bad-with-applicationfiledialog?forum=exceldev including this comment:
  "Does your code do any (un)protecting of worksheets or the workbook? If so, please be aware that changing protection has slowed down by a factor of as much as 2000 since the upgrade to Office 2013, due to a change in the password hash algorithm."