Re: Explaining single level store to non i people

Nathan wrote:

You argue that wide pointers add overhead, consume more memory, and
negatively impact performance. But Frank Soltis asserts that SLS
significantly improves performance in multi-user, multi-tasking
settings.

Take the idea of multiple users running the same application, but
each instance of the application in a separate process. There may be
many jobs running, but never more than one instance of application
code and data in memory under SLS, which IIRC greatly reduces the
conventional overhead of each process allocating its own space for
code and data, and the conventional overhead of switching between
jobs.

Actually, that's how things work in Linux too. To quote from the book
"Beginning Linux" (Cox, Matthew, Stone; published 2003):

"Typically, a Linux system will share code and system libraries among
processes so that there's only one copy of the code in memory at one
time."

That may not appeal particularly to those who may be deploying
applications under a single J2EE application server. It may not
appeal to those who may be deploying applications on one machine and
a DBMS on another.

But that REALLY appeals to those of us who use native languages
and interfaces that take advantage of that architecture.

As I said before, there's nothing in any language native to the iSeries
that depends on single-level store. Your RPG programs could just as easily
run on a conventional operating system. (Or could if a compiler existed.)

Cheers! Hans