Skip to content
Thoughtful, detailed coverage of everything Apple for 32 years
and the TidBITS Content Network for Apple professionals

Summing It Up

Properly written INITs shouldn’t exhibit any of the above stated problems. But if your Macintosh needs a little tweaking to get it working smoothly again, there is nothing wrong to giving a little more memory to the System Heap. In no case should you ever have to allocate more than 50K of extra memory to your System Heap. After a point, no amount of fudging will save you. Try to identify the culprit INIT that causes problems, and trash it. Or better yet, make sure you have the latest version of every INIT you use. Realize that INIT crashes/conflicts do not stem from lack of System Heap memory, but from improperly written software. Giving the System Heap extra memory may circumvent some problems, but it is not the source of them.

When you choose "About the Finder" from the Apple Menu, there should be a little bit of white space (free memory) in the "System" memory bar. 5-10% or so should be fine.

With that in mind, here are a few recommendations. INITs are particularly sensitive pieces of code, so expect them to be upgraded more frequently then other software products, and keep up with the current versions. Your Macintosh will be more stable if you use the current versions of the INITs you use, and if you use INITs only from well known and established vendors who support their products. Taking these precautions will result in a far more stable Macintosh than any amount of System Heap tweaking ever could.

20K – 50K of extra System Heap space (free System Heap memory), OK. That is a nice margin of error. More than that? Forget it, tell them to fix it!

If you are interested in increasing the size of your System Heap, here are three free programs that manually adjust System Heap size:

Heap Fixer
BootMan
Heap Tool

Contact the author at:

Andrew Welch
Mark 3 Software
29 Grey Rocks Road
Wilton, CT 06897

…and if you include a disk and a self-addressed, stamped mailer, I will send you the latest versions of my shareware programs!

Subscribe today so you don’t miss any TidBITS articles!

Every week you’ll get tech tips, in-depth reviews, and insightful news analysis for discerning Apple users. For over 31 years, we’ve published professional, member-supported tech journalism that makes you smarter.

Registration confirmation will be emailed to you.