[comp.sys.dec] SCSI to DECSystem 5400

ojala@cs.hut.fi (Petri Ojala) (01/22/91)

DEC has SCSI adapter KZQSA for Q-bus available for DAT- and CDROM-devices.
Has anyone tried using SCSI disks on this particular SCSI adapter ?
(The generic kernel configuration file seems to say that sii0 supports
disks)  The environment is DECSystem 5400 running Ultrix 4.1.

What other alternatives does there exist to get SCSI support for
DECSystem 5400 ?  Third-party suppliers ?  How is the device driver
support ?

Thank you for possible answers.  I'll summarize if necessary.

Regards,
Petri Ojala
ojala@fuug.fi

rwood@wsl.dec.com (Richard Wood) (01/29/91)

Ojala@cs.hut.fi (Petri Ojala) writes:
|> 
|> DEC has SCSI adapter KZQSA for Q-bus available for DAT- and CDROM-devices.
|> Has anyone tried using SCSI disks on this particular SCSI adapter ?
|> (The generic kernel configuration file seems to say that sii0 supports
|> disks)  The environment is DECSystem 5400 running Ultrix 4.1.
|> 
|> What other alternatives does there exist to get SCSI support for
|> DECSystem 5400 ?  Third-party suppliers ?  How is the device driver
|> support ?

The best solution (although possibly impracticle due to budget
constraints) would be to upgrade to a DECsystem 5500.  There are
substantial gains:

	- CPU performance approximately doubles, to 21.5 SPECmarks
	  (from somewhere around 11 or so)

	- "PrestoServe" synchronous file system accelerator
	  *dramatically* speeds up write access to any synchronous
	  mounted file system, notably including NFS server disks.

	- A single SCSI channel is bundled in, along with the 5400's
	  DSSI and Q-bus based storage methods.

-- ---------------------------------------------------------------------
Richard Wood     Corporate Worksystems Team      Digital Equipment Corp.
========================================================================

vixie@decwrl.dec.com (Paul A Vixie) (01/29/91)

Richard,

>>	- "PrestoServe" synchronous file system accelerator
>>	  *dramatically* speeds up write access to any synchronous
>>	  mounted file system, notably including NFS server disks.

I keep meaning to ask Chet about this.  Do you know if the DEC PrestoServe
product allows asynchronous writes to local filesystems' inode and directory
blocks?  For Decwrl, that would be a big win since it creates and deletes a
lot of files per second.

I'm posting this to Usenet since I think the answer would be generally
interesting.  

Cheers,
--
Paul Vixie
DEC Western Research Lab	<vixie@wrl.dec.com>
Palo Alto, California		...!decwrl!vixie