ultrix 2.0 disk throughput

[Paul Lansky]

We have just upgraded to Ultrix 2.0 from 1.1, and I discover that our
disk throughput seems to be considerably slower.  Here is configuration
MicrovaxII, EmulexQD32, two Fuji Eagles.  
Under 1.1 and 2.0 kernel is modified to allow 16k MAXBSIZE file systems.
Under 1.1 we were able to get about 600k bytes per second. Under 2.0
rate is down to 250k bytes per second.  I didnt remake file systems under
2.0.  

This is serious problem since we need to do high-speed data acquisition.
Is it us, or is it 2.0?