too many instance performance degradation

[Altera_Forum]

I am using the Altera custom licensed version of Modelsim. 

 It is complaining that I have too many instances (5) and there will be a performance degradation.   And there is, it is unbelievably slow.  Too many instance of what??  What can I do about it??  Thanks, Don

[Altera_Forum]

I don't remember the exact message, but I got an error when I had more instances of modelsim running than I have cores on my CPU. Do you have extra modelsim simulation windows hanging around? If so close them. Modelsim uses lots of memory. Check you computers available memory against the system requirements for modelsim. You may need more memory if it's running slow. In any case, if your hard disk light is flashing when modelsim simulations are running, you need more memory.

[Altera_Forum]

I have the performance monitor up to check on that and I have plenty of memory. 16GB and I am using 6GB. 

 CPU usage is at about 20%  I get this message when I first load the project, before it runs.  I went back to the code (I am only using 16k LEs and a few multipliers, no special IP at all!) and I cut out everything I could get away with, recompiled and did NOT get the message.  Modelsim ran at an acceptable speed.  I then went back and did a restart and on the restart I got that message and Modelsim ran like a dog.  So I quit modelsim and simply restarted modelsim from scratch, reloaded the project: NO MESSAGE!  And it ran fine. Does it have something to do with restarts from within modelsim. I have noticed a lot of other bugs too. Is this just another bug??  Thanks for your help, Don

[Altera_Forum]

--- Quote Start ---  I have the performance monitor up to check on that and I have plenty of memory. 16GB and I am using 6GB.  CPU usage is at about 20%  I get this message when I first load the project, before it runs.  I went back to the code (I am only using 16k LEs and a few multipliers, no special IP at all!) and I cut out everything I could get away with, recompiled and did NOT get the message.  Modelsim ran at an acceptable speed.  I then went back and did a restart and on the restart I got that message and Modelsim ran like a dog.  So I quit modelsim and simply restarted modelsim from scratch, reloaded the project: NO MESSAGE!  And it ran fine. Does it have something to do with restarts from within modelsim. I have noticed a lot of other bugs too. Is this just another bug??  Thanks for your help, Don  --- Quote End ---    Further work with modelsim shows that it still gets the error even with a small increase in project size.  This is a small project, how can altera charge money for something that won't even cover the code for one of their smallest fpgas?  Any help would be appreciated.  Thanks, Don

[Altera_Forum]

I did find statement "ModelSim-Altera Edition software supports designs of up to 3,000 instances. Instances from Altera's pre-compiled libraries do not count towards the 3,000 instance limitation." in the discussion of the various versions of modelsim at https://www.altera.com/products/design-software/model---simulation/modelsim-altera-software.html Could that apply?  

 I don't use restart myself. I tell it how long to run the simulation and always wait for it to finish. Then if I need another run I just start simulation again.

[Altera_Forum]

It just another Modelsim bug. Try simulating even smaller parts of your system. And hey, if restarting modelsim helps you then do it. 

I'm using the old Modelsim from Quartus 10.1 (that is the less buggy version that I know of, and I've been doing this for some years now) and I use "make; restart-f; run -all" whenever I want to restart simulation.