Maybe it's more a warning than a true question ?
I have written a rather heavy-duty code in Maple 2015. A few years ago I faced strong problems of increases in memory. After some investigations I found there came from a procedure P in which a loop realizes a few tenth of calls to fsolve.
This same procedure P was itself called a large number of times.
To try to fix them I inserted a forget(fsolve, initialize=true) command after the fsolve command.
At the end this didn't prove to be very efficient and I decided to rewrite some part of the code in a more efficient way. Basically the procedure P is now called only a few times but its inner loop is executed about 200 hundred times.
This new version of the code no longer presents memory size problems, while being more efficient from a computational time point of view.
Today procedure P still contains the forget(fsolve, initialize=true) command (I had forgotten to remove it)
Now I keep developping this same code under Maple 2018.
The Maple 2015 and Maple 2018 versions both return the same results, but the procedure P runs in about 20 times the time it runs in Maple 2015 (40 seconds instead of 2)
This comes from the 200 forget(fsolve, initialize=true) calls which consumme about 38 seconds.
With Maple 2015 these same 200 calls to forget(fsolve, initialize=true) only consumme 0.5 second:
As a cure I remove the forget(fsolve, initialize=true) command, plain and simple.
But maybe this misadventure could reveal an unseen behaviour of Maple 2018 ?