MicroVAX 3100/20 is apocalyptically slow even with 32MB of RAM

[Daniel Seagraves <dseagrav%lunar-tokyo.net@localhost>]

I have a MicroVAX 3100/20 with 32MB of RAM that once ran NetBSD many years ago. I recently had occasion to replace its disk and install 10.1, and it is superlatively slower than I remember it being. It’s so slow that it’s been trying to just bootstrap pkgsrc for about a week now, with pauses to allow the daily cron script to complete otherwise it won’t complete in less than 24 hours. The system time loses about 10-15 minutes a day, presumably because it can’t keep up with the clock interrupts. This is after I copied the GENERIC kernel config, stripped out all of the VAX models and devices that weren’t needed, and stripped out all of the RAM-based filesystems.

I don’t think RAM is the issue because I haven’t seen it go above 12-14MB active in top. It uses more swap than it does RAM.

Is there something configuration-wise I should try, or is this model just too slow to be supported anymore?