This article is from a FAQ concerning SCO operating systems. While some of the information may be applicable to any OS, or any Unix or Linux OS, it may be specific to SCO Xenix, Open This is an old article about SCO Unix and is only left here for historical purposes. There is lots of Linux, Mac OS X and general Unix info elsewhere on this site: Search this site is the best way to find anything.
The OS tries to flush the cache before sizing memory. On some systems, this may cause problems including painfully slow memory sizing. For Unix 3.2v4.2 and related systems, try adding the cache=/d option to your boot string. Try it out manually first, using defbootstr cache=/d at the Boot: prompt; if that works, add it to /etc/default/boot.
If you still run into problems, you may need to compare the memory map with and without cache. Boot with the cache=/d prompt options and, when the prompt comes up, type v to see the memory map found with the cache disabled. Then boot using cache=/e prompt and, again, type v at the prompt to see the memory map with the cache enabled. If they differ, it is not safe to size memory with cache disabled, and you will have to suffer with slow boot times (it will not affect performance once the system is rebooted).
If you found something useful today, please consider a small donation.
Got something to add? Send me email.
By understanding a machine-oriented language, the programmer will tend to use a much more efficient method; it is much closer to reality. (Donald Knuth)