Re: Difference between AS/400 and any normal web server

Hello Nathan,

Am 20.08.2022 um 15:14 schrieb Nathan Andelin <nandelin@xxxxxxxxx>:

The biggest difference from my perspective is that the native environment supports an native application architecture where all software runs in the same address space on a single scalable server as opposed to a distributedsapplication architecture, where web servers, application servers, and database servers typically run on separate servers.

Allow me to elaborate to explain "native mode" to someone who apparently doesn't know much about IBM i.

Native mode means what is "the other environment", not PASE, as described in my direct reply to the OP Jerry Ven. It's also often called "CL Environment", because its native command shell is "CL", or "Command Language".

To utilize the full capabilities of IBM i would mean to have each and everything run in the CL environment. In practice, not many UNIX applications can (hand have!) easily been ported to there, because software written on Linux/UNIX assumes a *lot* of things which aren't applicable to the CL environment (or IBM i in general). Ask for details if interested. A lot of my personal experience on that topic with OS release V4R5 appears to be still valid.

I'm not sure if Apache on i in recent releases is a PASE, or a CL thing. (The older "IBM Web Server" on V4 was running in CL.) As far as I've understood, PHP is running in PASE only. The OS integrated database DB2 is running "in CL" (not exactly, but for the sake of initial simplicity I'll leave it at that), but access to it AFAIK needs to go through a local ODBC connection. DB2 has many differences to MySQL: Data Types, SQL syntax, etc. Unfortunately, MySQL is assumed the database of choice on Linux by many popular PHP based OpenSource projects, such as MediaWiki, or WordPress. Little of those implement generic ODBC access for databases which would enable using DB2 with little or no code change at all.

IBM once released a version of MySQL which used DB2 tables as storage backend. According to some list members, it was clumsy to use and left a lot of performance to be desired. I don't know what happened to it. I assume IBM silently dropped support for it.

Maybe there is a PASE port of MySQL, which might enable you to run existing applications insisting on MySQL, on IBM i. I highly question going that route, because the main reason to spend money for IBM i *is* the DB2 database, its capabilities stemming from the "OS integrated" approach, and its performance and reliability.

:wq! PoC