Re: Is IPL necessary?

["Paul Morgan" <pmorgan@xxxxxxxxxxxxxx>]

A little story:

I was working at Builder's Square back in 1988.  Being a subsidiary of KMart
and maxed out on our S/38s we were a Beta site for the original AS/400 B60.
We'd IPL our S/38 and AS/400 every weekend to avoid running out of temporary
address space.  The S/38 and AS/400 would crash and crash hard when the
temporary address space was used up.  The B60 kept crashing like clockwork
every Friday and couldn't make it to the next weekends IPL.  Looking at the
temporary address space on a Friday would show the temporary address space
used at about 70%.  The system should have easily been able to get through
to the Saturday night IPL.  Instead it would crash that afternoon requiring
a rebuild of indexes for the next day or two.

Turned out we were blowing an internal temporary address table limit instead
of the temporary address space limit.  Our large number of remote display
terminals in all the stores made heavy use of the communication subsystems.
The communication subsystem would create very small objects of 4 bytes which
wouldn't take up much of the temporary address space but did take up an
entry in the internal temporary address table.  We'd fill up the table and
crash before running out of address space size.

Paul

-- 
Paul Morgan
Senior Programmer Analyst - Retail
J. Jill Group
100 Birch Pond Drive, PO Box 2009
Tilton, NH 03276-2009
Phone: (603) 266-2117
Fax:   (603) 266-2333

"Al Barsa" wrote

> Older CISC systems and System/38's had 48 bit addressing, and could run
out
> of addresses if not IPLed regularly.