Swatch helps you track down heap bugs. It’s also lotso fun to watch.
To install Swatch, move Swatch INIT and Swatch Riff into your System Folder and reboot. Then run Swatch and watch.
Colors indicate the four different heap blocks shown. Red is for non-relocatable (NewPtr) or relocatable-but-locked blocks. Yellow is for relocatable blocks. Orange is for purgeable relocatable blocks (essentially free). Green is free memory. (If you are using black & white, the colors are replaced by the patterns black, gray, barbershop and white.)
Zoom in on a heap by clicking on it (the magnifying glass cursor). Hold the option key down and click to zoom out. Hold the command key down and click to display the memory address at that location.
Click on a heap name (System, Backgrounder, etc.) to purge and compact a heap. Surprisingly, my machine still functions after doing this to the System heap!
Click on the MacsBug icon in the lower-left to drop into MacsBug and display some useful info. With a zone address showing next to the bomb, MacsBug will switch to that heap upon entering (";HX zone"). With a memory address showing, MacsBug will switch to that heap and give you some info about that address (";HX zone;WH address"). This is great for tracking down unknown blocks.
Swatch saves your window’s location and heap zoom factor in a file called “Swatch Prefs” in your System Folder.
The Swatch INIT patches _OpenResFile and _CloseResFile in order to watch applications start up and shut down. It is small and very unobtrusive. Swatch Riff is used for Swatch’s (excessive) about box. Swatch works fine without it, in case hard disk free space is a concern.
Change the values in the ‘WNE ’ resource to affect how often Swatch updates. I use the values 2 and 15 and leave Swatch running always on my second monitor.
I’d like to add the ability to show certain resource types with special colors in the heap display (all CODE resources as purple, for example). I’d also like to add some kind of memory manager trap recording so that you can tell who created a block. I’d also like to add the display of zones created within heaps or on the stack. If you have any ideas, please let me know.
Have fun. Swatch is free.
joe holt
Adobe Systems Inc.
P.S. This is not an Adobe product, so please don’t bother our fine technical support people. If you have questions, contact me:
