Post-Install Optimizations

OS/400 provides a lot of default values for variables (affecting the run-time environment) and program options. Some of these make sense, some of them are kept consistent with earlier versions of the OS because of compatibility reasons.

Some of these recommendations might not be appropriate for you by various reasons. Don't apply blindly.

Housekeeping

These are settings and scheduled jobs to keep your system uncluttered.

Change unneeded programs to not run

We most likely don't need to run lpd and smtpd to run per default.

CHGLPDA    AUTOSTART(*NO)
CHGSMTPA   AUTOSTART(*NO)

You can easily check all settings at once by using STRDFU OPTION(5) on the file QUSRSYS/QATOCSTART. These are not needed in general. Depending on OS version, not all entries may be available.

• *DIRSRV
• *NETSVR
• *SLP

Cleanup unneeded stuff

These objects come by default at OS install time, are not needed to my knowledge, and thus can be safely deleted:

DLTOUTQ    OUTQ(QDKT)
DLTOUTQ    OUTQ(QPFROUTQ)
DLTOUTQ    OUTQ(QPRINTS)
DLTF       FILE(QPRINTS)
DLTOUTQ    OUTQ(QPRINT2)
DLTF       FILE(QPRINT2)
DLTOUTQ    OUTQ(QTPPPOUTQ)
DLTDEVD    DEVD(QESPAP)
DLTDEVD    DEVD(QIADSP)
DLTDEVD    DEVD(QIAPRT)
DLTDEVD    DEVD(QQAHOST)
DLTDEVD    DEVD(QTIDA)
DLTDEVD    DEVD(QTIDA2)
DLTCTLD    CTLD(QESCTL)
DLTCTLD    CTLD(QTICTL)
DLTLIND    LIND(QESLINE)
DLTLIND    LIND(QTILINE)

System Values

System values are like environment variables as known from common operating systems. They influence system operation. I recommend the following changes.

System Control

• Change work environment to separate subsystems for different kind of jobs.

CHGSYSVAL  SYSVAL(QCTLSBSD) VALUE('QCTL QSYS')

• Set automatic DST adjustment, and UTC offset. This value is valid for Central Europe (Berlin, Paris, …).

CHGSYSVAL  SYSVAL(QTIMZON) VALUE('QP0100CET2')

• Lessen time to automatically end disconnect interacive jobs (sessions).

CHGSYSVAL  SYSVAL(QDSCJOBITV) VALUE('60')

(Memory) Allocation

• Adjust automatic performance values only at runtime, not at IPL.

CHGSYSVAL  SYSVAL(QPFRADJ) VALUE('3')

• Make sure, database tasks can use system resources as needed.

CHGSYSVAL  SYSVAL(QQRYDEGREE) VALUE(*OPTIMIZE)

• Match jobs running in total with reservations at IPL time. See WRKACTJOB and set to slightly more than the Active Jobs value to be seen there.

CHGSYSVAL  SYSVAL(QTOTJOB) VALUE(80)

• Allow memory pools to self adjust depending on jobs running.

CHGSHRPOOL POOL(*BASE) PAGING(*CALC)
CHGSHRPOOL POOL(*INTERACT) PAGING(*CALC)
CHGSHRPOOL POOL(*SPOOL) PAGING(*CALC)

Message-and-Logging

• Allow immediate deletion of problem reports.

CHGSYSVAL  SYSVAL(QPRBHLDITV) VALUE(0)

• Do not log software errors. We can't do much about these anyway, seen from a hobbyist viewpoint.

CHGSYSVAL  SYSVAL(QSFWERRLOG) VALUE(*NOLOG)

• Maximize Central Syslog (viewable with DSPLOG size before rotation. Depending on OS version only VALUE(32767) may be valid.

CHGSYSVAL  SYSVAL(QHSTLOGSIZ) VALUE(*DAILY)

• Raise allowed unsuccessful sign on tries before taking action.

CHGSYSVAL  SYSVAL(QMAXSIGN) VALUE('15')

• Minimize logging for sessions disconnected beause of device errors.

CHGSYSVAL  SYSVAL(QDEVRCYACN) VALUE(*ENDJOBNOLIST)

Security System Values

• Unrestrict automatic creation of system objects triggered by external (network) requests.

CHGSYSVAL  SYSVAL(QAUTOVRT) VALUE(*NOMAX)

• Allow restore with all security relevant flags.

CHGSYSVAL  SYSVAL(QALWOBJRST) VALUE(*ALL)

• Allow QSYSOPR signon to all devices.

CHGSYSVAL  SYSVAL(QLMTSECOFR) VALUE('0')

• Raise maximum password length to maximum value.

CHGSYSVAL  SYSVAL(QPWDMAXLEN) VALUE(10)

• Raise minimum passsword length for security reasons.

CHGSYSVAL  SYSVAL(QPWDMINLEN) VALUE(8)

Misc

• PTF install shall be done on unattended IPL time.

CHGSRVA PTFINSTYP(*DLYALL)

• Provide European style formatting.

CHGSYSVAL  SYSVAL(QCURSYM) VALUE('€')
CHGSYSVAL  SYSVAL(QDECFMT) VALUE('J')
CHGSYSVAL  SYSVAL(QSRTSEQ) VALUE(*LANGIDUNQ)

• Allow background compiling in PDM.

GRTOBJAUT  OBJ(QGPL/QBATCH) OBJTYPE(*JOBD) USER(*PUBLIC) AUT(*USE)

• Tweaking automatic cleanup (like logrotate).

CHGCLNUP   ALWCLNUP(*YES) STRTIME('02:22:22') USRMSG(7) SYSMSG(3) SYSPRT(7) SYSLOG(14) CALITM(*KEEP)

• Change general SNA networking attributes. This is one long line. Take care to get it completely.

CHGNETA    ALRSTS(*ON) ALRLOGSTS(*LOCAL) ALRPRIFP(*NO)  ALRDFTFP(*NO) ALRBCKFP(*NONE) ALRRQSFP(*NONE) ALRCTLD(*NONE) ALRHLDCNT(0) ALRFTR(*NONE) JOBACN(*SEARCH) VRTAUTODEV(254) MDMCNTRYID(DE)

IPL Customization

With this procedure, the current startup program for the OS can be retrieved for easy customization.

RTVCLSRC   PGM(QSTRUP) SRCFILE(QCLSRC)
WRKMBRPDM  FILE(QCLSRC) MBR(QSTRUP) MBRTYPE(CLP)
CRTCLPGM   PGM(QSYS/QSTRUP)

Change Program Defaults

• File creation and change defaults.

CHGCMDDFT  CMD(CRTPF) NEWDFT('SIZE(*NOMAX *N *N) WAITFILE(*IMMED) WAITRCD(*IMMED) REUSEDLT(*YES)')
CHGCMDDFT  CMD(CHGPF) NEWDFT('DLTDEPLF(*YES) SIZE(*NOMAX *N *N) WAITFILE(*IMMED) WAITRCD(*IMMED) REUSEDLT(*YES)')
CHGCMDDFT  CMD(CRTLF) NEWDFT('WAITFILE(*IMMED) WAITRCD(*IMMED)')
CHGCMDDFT  CMD(CHGLF) NEWDFT('WAITFILE(*IMMED) WAITRCD(*IMMED)')

• No unnecessary wait for power down. CONFIRM(*NO) can be added for newer releases to suppress prompting.

CHGCMDDFT  CMD(PWRDWNSYS) NEWDFT('OPTION(*IMMED) ENDSBSOPT(*NOJOBLOG)')

Regular Cleanup jobs

See job comment TEXT for details. These are long lines. Take care to get it completely.

ADDJOBSCDE JOB(PRGPRB) CMD(DLTPRB STATUS(*CLOSED)) FRQ(*WEEKLY) SCDDATE(*NONE) SCDDAY(*ALL) SCDTIME('13:22:00') MSGQ(*LIBL/QSYSOPR) TEXT('Purge closed and deletable problem entries')
ADDJOBSCDE JOB(RCLTMPSTG) CMD(RCLTMPSTG DAYS(30)) FRQ(*MONTHLY) SCDDATE(*MONTHSTR) SCDDAY(*NONE) SCDTIME('13:24:00') MSGQ(*LIBL/QSYSOPR) TEXT('Reclaim temporary storage')
ADDJOBSCDE JOB(RTVDSKINF) CMD(RTVDSKINF) FRQ(*MONTHLY) SCDDATE(*MONTHSTR) SCDDAY(*NONE) SCDTIME('13:34:00') MSGQ(*LIBL/QSYSOPR) TEXT('Retrieve disk space stats')
ADDJOBSCDE JOB(QPGMRCLR) CMD(CLRMSGQ MSGQ(QPGMR) CLEAR(*KEEPUNANS)) FRQ(*WEEKLY) SCDDATE(*NONE) SCDDAY(*ALL) SCDTIME('07:07:07') RCYACN(*NOSBM) MSGQ(*NONE) TEXT('Delete uninteresting messages')