Performance QZHQSSRV QZHQSRVD

[Rauh]

Hallo,

wir haben auf einer 520er V5R3 laufen. Seit kurzem arbeiten wir mit Dataqueues. Dabei haben wir immer wieder Probleme mit den Antwortzeiten. Es werden permanent kurzzeitige QZHQSSRV-Jobs unter dem Subsystem QSYSWRK gestartet, die das System stark belasten. Die die CPU Auslastung schwankt derzeit bei 80%.

Wer kennt diese Jobs und wie kann ich bei diesen Jobs die Last begrenzen?

Vielen Dank für's Antworten

Rauh

[Bruno Jakob]

Hallo Rauh,

Such doch mal im Info-Center:

*DTAQ: The Data Queue server daemon is started in the QSYSWRK subsystem. The daemon job is named QZHQSRVD. The associated server job is named QZHQSSRV. 

Wenn viel damit gearbeitet wird, ist es u. U. sinnvoll, die Anzahl der vorgestarteten Jobs zu erhöhen:

Use of Prestart Jobs
A prestart job is a batch job that starts running before a program on a remote system initiates communications with the server. Prestart jobs use prestart job entries in the subsystem description to determine which program, class, and storage pool to use when the jobs are started. Within a prestart job entry, you must specify attributes for the subsystem to use to create and to manage a pool of prestart jobs.

Prestart jobs increase performance when you initiate a connection to a server. Prestart job entries are defined within a subsystem. Prestart jobs become active when that subsystem is started, or they can be controlled with the Start Prestart Job (STRPJ) and End Prestart Job (ENDPJ) commands.

System information that pertains to prestart jobs (such as DSPACTPJ) uses the term 'program start request' exclusively to indicate requests made to start prestart jobs, even though the information may pertain to a prestart job that was started as a result of a sockets connection request.

    Notes:

        * Prestart jobs can be reused, but there is no automatic cleanup for the prestart job once it has been used and subsequently returned to the pool. The number of times the prestart job is reused is determined by the value specified for the maximum number of uses (MAXUSE) value of the ADDPJE or CHGPJE CL commands. This means that resources that are used by one user of the prestart job must be cleaned up before ending use of the prestart job. Otherwise, these resources will maintain the same status for the next user that uses the prestart job. For example, a file that is opened but never closed by one user of a prestart job remains open and available to the following user of the same prestart job.
        * By default, some of the server jobs run in QUSRWRK or QSERVER. Using iSeries Navigator, you can configure some or all of these servers to run in a subsystem of your choice.
             1. Double-click iSeries Navigator --> Network --> Servers --> iSeries Access.
             2. Right-click the server that you want to configure subsystems for and select Properties.
             3. Configure the server using the Subsystems page.
          If you move jobs from the default subsystem, you must:
             1. Create your own subsystem description.
             2. Add your own pre-start jobs using the ADDPJE command. Set the STRJOBS parameter to *YES.
          If you do not do this, your jobs will run in the default subsystem.

All of the OS/400 servers that are supported by the sockets communications interface support prestart jobs.
These servers are:

Network print server
Remote command and distributed program call server Central server
Database server
Secure Database server
File server
Secure File server
Data Queue server
Signon server (unique to servers using sockets communications support) 

Bruno