Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!pasteur!ames!sun-barr!male!pitstop!jwest
From: jwest@pitstop.West.Sun.COM (Jeremy West)
Newsgroups: comp.arch
Subject: Re: The IPI fast peripheral interface
Summary: Sun's own controller
Message-ID: <655@pitstop.West.Sun.COM>
Date: 4 May 89 12:11:44 GMT
References: <12478@reed.UUCP> <128@melba.oz>
Organization: Sun Microsystems, Mt. View, CA
Lines: 23

In article <128@melba.oz>, gnb@melba.bby.oz (Gregory N. Bond) writes:
> 
> 
> The new Sun servers (SPARCservers?) use IPI disks for the high end
> boxes, according to the product launch here yesterday.  This would
> indicate that they are faster even than SMD disks on the VME bus. 
> 
> How does Sun do the IPI host adapter?
> 

Sun has its own design of IPI controller on a 9U VME card.
It has an on-board 68020 and 1 Mb of read-ahead cache and has some good
optimisation algorithms. It can take faster disks than are currently available
and does fast burst accesses on the VME bus. Throughput is about
twice as good as SMD, cabling is simpler, up to 8 drives per controller
and 4 controllers per system with 1 Gb (formatted) drives to give max of
32 Gb on SPARCserver390 systems. Price is similar to SMD.

Adrian Cockcroft
Sun Cambridge UK TSE
sun!sunuk!acockcroft

(Borrowing Jerry West's account at Mountain View to get at USENET)