Dear Bill,

The reason I ask is we are having trouble with the 3995 (C64) in Roll
Forward mode.  I wrote this up to the newsgroup in another memo so
forgive me if I am repeating myself.  As you probably know, when your
recovery log reaches the trigger that has been set for roll forward, a
database backup is prompted.  When complete, the recovery log size is
again reduced.

My database is backing up to optical platters on the 3995.  The event
that I have encountered is that, despite the fact that a dbbackup
supposedly has priority over any other ADSM process, if I have all
drives of the 3995 occupied doing other (ADSM) things when a dbbackup is
triggered, none of these processes suspend to give my dbbackup a drive
to perform its operation.

When I first called support, they said that the unit was not functioning
per ADSM Specification but they recanted and said that the specification
for this action, though described as a function of a "library" in
everything I've ever seen, is only a spec for a TAPE library and not an
OPTICAL library.

I don't buy this.  Have you ever seen this?

Thanks,

Hilary Whitehead
IBM Global Services

> -----Original Message-----
> From: Bill Quintrell [SMTP:Bill_Quintrell AT PROVIDENTCOMPANIES DOT COM]
> Sent: Thursday, June 11, 1998 1:38 PM
> To:   ADSM-L AT VM.MARIST DOT EDU
> Subject:      Re: 3995 Optical Library
>
> Bill Quintrell@PROVIDENT LIFE
> 06/11/98 04:37 PM
> We have one...
>
> We have a 3995-C68 attached to an RS/6000 and being managed by ADSM as
> a
> large on-line cache for our imaging system (the permanent archive
> documents
> are on ADSM/MVS tape).
> We have a second/redundant unit set to arrive here on the 16th of this
> month (we could not wait for the double-capacity model).  We currently
> have
> 4 million items and add about 6,000 per day.  At this rate, it will be
> full
> around January.  We expect to apply an upgrade and purchase new media
> at
> that time.  I hope it is not too tedious to slowly exchange the media
> and
> let ADSM move to then newer capacity...
>
> Our goal is to only access it for documents that are not in our DASD
> cache.
> The less we access the 3995, the better we are doing.  As such, we
> generate
> about 120 read mounts per day.  As for writes, ADSM is set to never
> "fill
> up" it DASD to require a write mount during the day.  At night, we set
> the
> threshold down to force a "drain" to the optical media and then raise
> it
> back up for the next day's processing.
>
> We have been using the unit since last November and have never had to
> repair/adjust anything - it works.