| Title: | DECWINDOWS 26-JAN-89 to 29-NOV-90 |
| Notice: | See 1639.0 for VMS V5.3 kit; 2043.0 for 5.4 IFT kit |
| Moderator: | STAR::VATNE |
| Created: | Mon Oct 30 1989 |
| Last Modified: | Mon Dec 31 1990 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 3726 |
| Total number of notes: | 19516 |
A customer is developing their mapping application on VS3520 with 24
planes and 16 MB memory. Their application will open a window with size
about 1000x1000 that display a portion of a huge imaging map which is
composed of hundreds of image files each with size 360x480 pixels. They
also want to implement scroll-bar function on the window.
But they are running out of memory even their working set parameters
been enlarged to 20000! The map displaying speed is very slow! The
program can't even link when they try to open more memory buffer to
hold extra images.
Q: Is it possible to reduce the memory size the map would take? Because
their map is originally displayed on PC which use 5 bits to represent Red,
Green, Blue intensity each. Now they're using VS3520 with 24 planes.
They found that the image structure they created is 32 bits_per_pixel.
Is it possible to reduce to 15/16 bits_per_pixel?
Q: How much memory should they have on VS3520? 32, 64 or more?
Q: Is there any suggestion/idea for their program development so that
their application won't take too much memory while still remain good
performance?
Q: Could double-buffer help them to improve their application
performance?
Thanks for any help!
Johnny
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 3199.1 | DECWIN::FISHER | Locutus: Fact or Fraud? | Mon Aug 13 1990 11:13 | 8 | |
"Running out of memory". If they are running out of virtual memory, working set does not help. WS may reduce the amount of paging, but not the total amount of VM they have. What they need is a larger Page File Quota for the account they are doing this on (or sysgen parameter PQL_*PGFLQUOTA for the whole system) and also sysgen parameter VIRTUALPAGECNT. Don't forget to make these changes in modparams.dat and run autogen rather than just jamming them into SYSGEN Burns | |||||
| 3199.2 | Watch display memory | TOOLEY::B_WACKER | Mon Aug 13 1990 14:48 | 9 | |
> Q: Is it possible to reduce the memory size the map would take? Because > their map is originally displayed on PC which use 5 bits to represent Red, > Green, Blue intensity each. Now they're using VS3520 with 24 planes. Yes, they would save display memory by creating pixmaps with miminum depth and using something like XCopyPlanes to make them visible. If you exceed display memory it pages to ram and becomes very slow. Bruce | |||||