My memory is that the Alpha and OSF/1 hit at the same time. OSF/1 had a different model of shared library stuff, and I recall it being something which sometimes demanded a reboot to get a runtime cache rebuilt/linked so things worked as you expected. I may be mis-remembering, I think DEC had coded some pull up smarts to optimise the lib -> indirect -> actual call path into the shortest path possible.

I also recall the syslog being absolutely FLOODED with "unaligned access at..." messages.

It was fast. It was very fast. If you knew how to make the compiler to the precompile, test run, introspect, recompile cycle, it would work out from some sample state the right choices (branch prediction ordering?) and make your fast code even faster.