Anssi, I suggest that you go to View-Select Columns and add "Peak Memory Usage" to your Task Manager process display.
This will show you the maximum real memory ever used by each task as well as the current real memory used by each task. When I run a J task and create a large noun, I see the space use peak in both "Mem Usage" and "Peak Mem Usage". If I create a second J task and create a second large noun, so that the sum of the space required is more than the real memory available, I see the second J task "Mem Usage" size increase to what it needs and the first J task "Mem Usage" decreases to a small number. The "Peak Mem Usage" continues to reflect the maximum working set size for both J tasks. During the increase in real memory usage in the second J task, I saw a spike in paging activity and an overall decrease in system performance that improved somewhat when the second task got the real memory it needed. The bottom line is that, even though J continues to reserve the 1.6GB of virtual memory, if J is not actively using it, the real pages should get paged out relatively quickly and allow the real memory to be used by other tasks. -- David Mitchell On 2/22/2010 8:14, Anssi Seppälä wrote: > XP64. The other memory-hungry application is in J. With mapped files the > release of the mapping immediately shows in the Task Manager. I want to be > sure that J releases all memory before starting another memory hungry task. > Also 7!:0 shows the memory used, but ,I do not see any change after clearing > all names from 7!:0. > > > > Anssi > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of bill lam > Sent: 22. helmikuuta 2010 12:45 > To: [email protected] > Subject: Re: [Jprogramming] Garbage collect J request > > lun, 22 Feb 2010, Anssi Seppälä skribis: >> How can I ask J to reduce the memory as seen in the Windows Task Manager? > My >> J session uses (J64) , say, 1.6GB memory and after clear '', the 1.6GB >> remains but there is no names and locales. If I close the session and >> reopen, the memory is 25MB. >> Anssi >> > > Did you test it under vista or win7? If so, there might be nothing to > be worried. You can confirm by running another memory hungry task to > eat that 1.6GB and see whether disk swapping will be started or not. > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
