I'm trying to understand how the various 7!:n foreign conjunctions relate to 
each other and to the memory use reported by Windows Task Manager. I apologise 
in advance if any of the questions below illustrate my meagre understanding of 
memory usage.

>From the Dictionary (help/dictionary/dx007.htm)
7!:0 Current. Space currently in use.
7!:3 Free Space. ... 2-column table of the block sizes and number of free 
blocks for each size.
7!:6 Locale Space. The space in bytes used by the locales named in y , 
including the space for the names as well as values in the locale, locale name, 
path, hash table, and global symbol table entries.

My understanding from reading through the posts linked here:
http://www.jsoftware.com/jwiki/Guides/General_FAQ/How_does_J_manage_memory%3F

..is that the space described by 7!:3 is allocated to and managed by J (not 
available to the operating system), but not currently "used" by J.

A) Is Free Space included in, or on top of Current space ?

   ]LocSpc=: +/ 7!:6 conl ''
1218784
   ]FreeBlks=: 7!:3 ''
  64 1411
 128  602
 256  303
 512  109
1024   21
   ]FreeSpc=: +/ */"1 FreeBlks
322240
   ]InuseSpc=: 7!:0 ''
1465472

   InuseSpc-LocSpc+FreeSpc
_75552
...suggests that it is on top of 7!:0 '',

B) Assuming Free Space is on top of Current Space, what else is included in 
Current Space apart from Locale Space?

   InuseSpc-LocSpc
246688

Again assuming that FreeSpc is on top of InuseSpc, total space allocated to J 
in kilobytes is:
   1024%~ InuseSpc+FreeSpc
1745.8125
Windows Task Manager reports 3,800 K in use.

C) Is the difference between Current Space + Free Space and what the Task 
Manager reports due to (from Dec 2001 forum post) "interpreter memory use 
including things like primitives and locales (symbol tables and namespaces)" ?

7!:1 Session. Total space used since start of session.

D) Is Session Space equal to Current space + all space allocated and then freed 
since the start of session?
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