Tuning your iSeries for Java SQL Database access...

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Hi all,

I put this together from some IBM pages.  If you are using JDBC and SQL
from a server that is not the AS/400, and accessing the iSeries data or
resources, you want to TUNE the system to support this kind of
Client/Server system access...  You need to put the Subsystems you are
using into their own memory pool and potentially configure them to meet
the access needs you are using...

One Specialist's Recommendation:  Put QSYSWRK, QUSRWRK and QSERVER in a
memory pool and give it at least 100 MB.  Watch performance and tune
accordingly.

Kristen Henry
303-883-0144

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Subsystems Used for Server Jobs
The server jobs are configured to run in different subsystems, depending
on their function. The following are the subsystems used for the server
jobs.

QSYSWRK
All of the daemon jobs (with the exception of the file server daemon job
and the database server daemon job) run in this subsystem. The file
server and database server daemon jobs run in the QSERVER subsystem.

QUSRWRK
This subsystem is where the server jobs run for these servers:

Network Print
Remote Command/Program Call
Central
Data Queue
Signon
Database

QSERVER
The file server, its associated daemon job and the database server
daemon job must run in this subsystem.

If this subsystem is not active, requests to establish a connection to
the file server or the database server will fail.

==================================================================
Server daemons
The server daemon is a batch job associated with a particular server
type. There is only one server daemon for each of the different server
types (such as database, network print, and signon). Each server type
has a one-to-many relationship between its server daemon and the actual
server jobs; one server daemon potentially has many associated server
jobs.

The server daemon allows client applications to start communications
with a host server that is using sockets communications support. The
server daemon does this by handling and routing incoming connection
requests. Once the client establishes communications with the server
job, there is no further association between the client and the server
daemon for the duration of that server job.

All server jobs (except file servers) ship running in the QUSRWRK
subsystem. The file server jobs run in the QSERVER subsystem. To use the
prestart jobs for the database daemon, QUSRWRK must be active.

The Start Host Servers command starts server daemon jobs. The server
daemons must be active for client applications to establish a connection
with a host server that is using sockets communications support.

If you are starting the database daemons or the file server daemons, the
QSERVER subsystem must be active. If you start any of the other server
daemons, the QSYSWRK subsystem must be active. To use the prestart jobs
for the server daemons that run in the QSYSWRK subsystem, QUSRWRK must
be active.

Server Mapper Daemon
The server mapper daemon is a batch job that runs in the QSYSWRK
subsystem. It provides a method for client applications to determine the
port number associated with a particular server.

This job listens on a well-known port for a connection request from a
client. The well-known port number for TCP/IP is 449. The client sends
the service name to the server mapper. The server mapper obtains the
port number for the specified service name from the service table. The
server mapper returns this port number to the client, ends the
connection, and returns to listen for another connection request. The
client uses the port number returned from the server mapper daemon to
connect to the specified server daemon.

The server mapper daemon starts with the STRHOSTSVR command and ends
with the ENDHOSTSVR command.

===========================================================

Starting host servers
To start the OS/400 Host Servers, use the STRHOSTSVR CL command. This
command starts the host server daemons and the server mapper daemon. It
also attempts to start the prestart job associated with that server.

Note: You can use Operations Navigator to configure your system so that
servers start automatically when you start Transmission Control Protocol
(TCP) with the STRTCP command. Newly shipped systems will do this by
default.

Each host server type has a server daemon. There is a single server
mapper daemon for the system. The client PC application uses the port
number to connect to the host server daemon. The server daemon accepts
the incoming connection request and routes it to the server job for
processing.

STRHOSTSVR command values:

SERVER

*ALL
Starts all host server daemons and the server mapper daemon.
*CENTRAL
Starts the central server daemon in QSYSWRK subsystem. The daemon job is
QZSCSRVSD, and the server prestart job is QZSCSRVS.
*DATABASE
Starts the database server daemon in QSERVER subsystem. The daemon job
is QZDASRVSD, and the associated server prestart jobs are QZDASOINIT,
QZDASSINIT, and QTFPJTCP.
*DTAQ
Starts the data queue server daemon in QSYSWRK subsystem. The daemon job
is QZHQSRVD, and the associated server prestart job is QZHQSSRV.
*FILE
Starts the file server daemon in QSERVER subsystem. The daemon job is
QPWFSERVSD, and the associated server prestart jobs are QPWFSERVSO,
QPWSERVSS, and QPWFSERVS2.
*NETPRT
Starts the network print server daemon in QSYSWRK subsystem. The daemon
job is QNPSERVD, and the associated server prestart jobs are QNPSERVS
and QIWVPPJT.
*RMTCMD
Starts the remote command and the distributed program call server daemon
in QSYSWRK subsystem. The daemon job is QZRCSRVSD, and the associated
server prestart job is QZRCSRVS.
*SIGNON
Starts the signon server daemon in QSYSWRK subsystem. The daemon job is
QZSOSGND and the associated server prestart job QZSOSIGN.
*SVRMAP
Starts the server mapper daemon in QSYSWRK subsystem. The daemon job is
QZSOSMAPD.
Note: If the daemon job runs in the QSYSWRK directory, the associated
server prestart jobs will run in the QUSRWRK directory by default.
Additionally, database server prestart jobs will run in QUSRWRK
subsystem by default.

Optional parameter:

RQDPCL
*ANY
At least one of the possible communication protocols must be active. If
none are, you get the PWS300D error message, and the daemons will not
start. You also get a diagnostic message (PWS3008 or PWS300F). This is a
Single Value.
*NONE
No communication protocol must be active. No messages appear. This is a
Single Value.
Specific protocol values

*TCP
Transmission Control Protocol/Internet Protocol (TCP/IP) must be active.
If it is not, you get diagnostic message PWS3008 and escape message
PWS300D. The daemons will not start.

*IPX
The IPX communication protocol must be active at the same time the
STRHOSTSVR command is issued. If IPX is not active, diagnostic message
PWS300F and escape message PWS300D will be issued and the host server
daemons will not be started.

Here is a STRHOSTSVR example.:

Specification of one required protocol:

STRHOSTSVR SERVER(*ALL) RQDPCL(*TCP)

This command starts all the host server daemons and the server mapper
daemon in QSYSWRK subsystem, as long as TCP/IP is active.

============================================

Database server
The database server allows clients access to the functions included with
DB2/400. This server provides:

Support for remote SQL access
Access to data through ODBC interfaces
Database functions (such as creating and deleting files and adding and
removing file members)
Retrieval functions for obtaining information about database files that
exist on the system (such as SQL catalog functions)

The programs listed in the following table are included with this
server.

Database server programs:

Program name   Library  Description
QZDASOINIT     QSYS     Server program
QZDASON2       QSYS     Sockets setup program
QZDASRVSD      QSYS     Daemon program
QZDASSINIT     QSYS     SSL server program

Note: The *PGM objects QZDANDB, QZDAROI, QZDASQL, and QZDACMDP are used
by the database server.

Additional information can be found at:

http://publib.boulder.ibm.com/html/as400/v5r1/ic2924/index.htm









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