[IBM APL2]
WA←⎕WA ⋄ A←1000 1000⍴1=1 ⋄ WA-⎕WA
125056
[GNU APL]
WA←⎕WA ⋄ A←1000 1000⍴1=1 ⋄ WA-⎕WA
48046080
APL2 obviously packs boolean ravels 8 bits per byte. How does GNU APL store its booleans?
I use large bitmaps a lot in my code, so having them stored packed in the workspace is a huge issue for me.