RP07-d & 4.2bsd

[tcs at usna.uucp]

>People running 4.2bsd on RP07's should be aware of the performance
>difference the RP07-d option can make.  

Your notes on the problems with the RP07 and RH780 were very
interesting, especially since our 11/780 has been running with the high
speed option since it was installed in Sept, 1983. The Jan-Mar 1983 VAX
Systems and Options catalog includes an RP07 system advertised as
supporting the 2.2Mb/s transfer rate (SV-AXVCB-CA).  This system was the
older one with the 16Kbit rams so it included the extra memory
controller.  The new 64Kbit memory systems (our configuration) are
actually a single SBI interface and two controllers, one for each bank
of memory.  I switched between the two modes of operation once when I
suspected a transfer rate problem (no difference noted w.r.t. the
problem).  The entire disk *MUST* be reformatted to write the correct
sector headers.

Our DEC serviceman also installed the system without the clock jumper.
It seems that all RP07's are shipped for interleaved operation.
If I hadn't been aware of the jumper he would have happily left the
system running at the 1.3Mb/s rate.  Section 2.5.2.3 Drive Characteristics,
page 2-27 of the RP07 user guide, is the only reference to it.

I havn't run the benchmark programs on the system.  Maybe when
I get another disk.
				Terry Slattery
				M/S 11G
				U.S. Naval Academy
				Annapolis, Md  21402
				301-267-4413
				tcs%usna at brl	(ARPA)
				decvax!brl-bmd!usna!tcs	(UUCP)