I have some maple procedures that worked fine for many years. However, I started to notice some important performance deterioration with the new versions (Maple 2021 and 2022). I could identify the "culprit", they are some simplify/sum commands like this one:
A := simplify( sum( sum( sum( sum(sum( sum( sum( sum(
,j1=1..N),k1=1..N),l1=1..N) ,i2=1..N),j2=1..N),k2=1..N),l2=1..N) );
Using, for instance, Maple 2017, this command requires to complete:
memory used=258.2MB, alloc=44.3MB, time=1.58
memory used=5247.1MB, alloc=394.0MB, time=39.35
memory used=16405.4MB, alloc=775.9MB, time=135.78
On the other hand, in Maple 2022 (similar results for 2021), we have
memory used=527.7MB, alloc=44.3MB, time=3.85
N := 6
memory used=10763.4MB, alloc=409.6MB, time=97.22
N := 7
memory used=34564.2MB, alloc=1139.9MB, time=351.94
My laptop (16G RAM) cannot execute N:=8 in Maple 2022 in reasonable time, I guess due to RAM limitation.
Does someone have any hint on how to improve the performance of these commands in Maple newer versions?