If we don't have lost clock interrupts, the only source of drift (assuming we don't have ntp or something else setting the system up for slow time adjustment), would be the chrystal itself. I know that the chrystal used in VAXen aren't perfect, and you do have some drift from that. But that is completely independent of load. But a drift of a couple of % would not be unexpected.Um, yes, it would be unexpected.
Yes, I agree - it would be unexpected. Which families of VAXen have clock drift? Neither my VAXstation 4000/30, nor my 4000/60, drift more than two seconds a day with NetBSD 9 or NetBSD 10. John