Question: How many custom words can be added before performance is affected?

[Gitoffthelawn]

Have you performed any metrics as to how many custom words can be added before performance is impacted?

Also, does the size of the text file open in Notepad++ make any difference to the answer?

I often work with 4-6MB text files and currently have about 6000 words I've added to my "custom word dictionary". I haven't noticed any big issues, but I'm wondering if I'm getting close or if I have plenty of room to grow.

BTW, for my primary dictionary I use the spelling dictionary included with Firefox. I wrote a little script to pull it out of omni.ja. The Mozilla dictionary is better than the Hunspell/Aspell dictionaries because it already includes a bunch of additional common words without having to create a dictionary with the SCOWL so large where it feels like almost every combinations of characters is recognized as a valid word. But even with those added words already added to the primary dictionary, my custom word list currents sits at around 6000 additional words.

[Predelnik]

I haven't measured but I use native hunspell mechanism for additional dictionary, so it should not be slower than regular dictionaries. I do think if any performance problems were to arise they should be addressed to Hunspell itself.