Every app starts very slow but only first time

[sandrokan]

Hi
my Imac has this strange and annoying feature. Every app takes about ten times longer to startup, the first time I open it (after boot).
For example, firefox takes 10-20 secs, Matlab takes 2 or 3 minutes, etc.

If I quit the app and I reopen it, it takes the normal time.

If I re-open the app after a long while, it takes forever again.

Another significant thing is that every operation that I perform inside that app takes much longer the first time.
For example, if I calculate the solution of an equation in Matlab, it takes a long while the first time, but it's enormously faster the second time.

It looks like there is something on the file system that slows down the apps, isn't it?

So far I tried to:
Check disk with disk utility (everything is ok)
Delete all caches
Give the related apps full disk permission.
PRAM reset
Issue is user-wide (every user has the same issue)
I have SSD, not HD.

Thank you for any suggestion
A

 

[lcubed]

is this a work machine which has HBSS installed (or other virus protection)?

HBSS on my iMac Pro turns matlab launches into a multi-minute event.

 

[sandrokan]

is this a work machine which has HBSS installed (or other virus protection)?

HBSS on my iMac Pro turns matlab launches into a multi-minute event.

Thanks

not that I am aware of. I inherited the machine from a previous employee. I upgraded to Catalina at the time, deleting old users and creating a new admin user.
But I don't think so. In our institute we don't use that software so it would be very unlikely she did install anything.