DB2 10 for Linux on System z Using z/VM v6.2, Single System Image Clusters and Live Guest Relocation

Chapter 4. DB2 Self-tuning memory manager and z/VM live guest relocation 25

Database Member 0 -- Database SAMPLE -- Active -- Up 0 days 00:00:02 -- Date

06/15/2012 01:40:31

Database Configuration Settings:

Description Memory Value Disk Value

DB configuration release level 0x0F00 0x0F00

Database release level 0x0F00 0x0F00

Database territory US US

Database code page 1208 1208

Multi-page File alloc enabled YES YES

SELF_TUNING_MEM ON ON

ENABLE_XMLCHAR YES YES

WLM_COLLECT_INT (mins) 0 0

DATABASE_MEMORY (4KB) AUTOMATIC(43824) AUTOMATIC(43824)

DB_MEM_THRESH 10 10

LOCKLIST (4KB) 4096 4096

MAXLOCKS 10 10

PCKCACHESZ (4KB) 1200 1200

SHEAPTHRES_SHR (4KB) 5000 5000

SORTHEAP (4KB) 256 256

DBHEAP (4KB) AUTOMATIC(1200) AUTOMATIC(1200)

CATALOGCACHE_SZ (4KB) 750 750

LOGBUFSZ (4KB) 256 256

UTIL_HEAP_SZ (4KB) 5000 5000

BUFFPAGE 1000 1000

APPL_MEMORY (4KB) AUTOMATIC(40016) AUTOMATIC(40000)

STMTHEAP (4KB) AUTOMATIC(8192) AUTOMATIC(8192)

APPLHEAPSZ (4KB) AUTOMATIC(256) AUTOMATIC(256)

STAT_HEAP_SZ (4KB) AUTOMATIC(4384) AUTOMATIC(4384)

4.3 DB2 LGR on a memory-constrained target cluster member

We have taken ITSOSSI3 and ITSOSSI4 z/VM members and configured them with 30 GB

and 8 GB of real memory, respectively. We relocated the DB2 Linux on the System z guest

from ITSOSSI3 (the member with more memory resources) to ITSOSSI4 where there is a

memory constraint. Also, to make the environment production-like, we have other guests

loaded on to the ITSOSSI4 member with their respective workloads running. The z/VM

environments for STMM are shown in Figure 4-1 on page 26.

Important: On Linux operating systems, although the ipcs command can be used to list all

the shared memory segments, it does not accurately reflect the amount of resources

consumed. You can use the db2mtrk command as an alternative to ipcs.

26 DB2 10 for Linux on System z Using z/VM v6.2, SSI Clusters and LGR

Figure 4-1 z/VM member environment for STMM

ITSOSSI4 member

Example 4-5 shows the details for the SSI cluster named ITSOSSIA and shows members of

that cluster, ITSOSSI1-ITSOSSI5.

Example 4-5 Cluster details

q ssi

SSI Name: ITSOSSIA

SSI Mode: Stable

Cross-System Timeouts: Enabled

SSI Persistent Data Record (PDR) device: SSIAC2 on 9E20

SLOT SYSTEMID STATE PDR HEARTBEAT RECEIVED HEARTBEAT

1 ITSOSSI1 Joined 06/19/12 14:24:45 06/19/12 13:19:06

2 ITSOSSI2 Joined 06/19/12 13:19:05 06/19/12 13:19:05

3 ITSOSSI3 Joined 06/19/12 13:19:07 06/19/12 13:19:07

4 ITSOSSI4 Joined 06/19/12 13:19:31 06/19/12 13:19:31

Ready; T=0.01/0.01 13:19:34

q stor

STORAGE = 8G CONFIGURED = 8G INC = 256M STANDBY = 0 RESERVED = 0

Ready; T=0.01/0.01 13:19:53

ITSOSSI3 member

Example 4-6 on page 27 shows the storage details for cluster member ITSOSSI3. Note that it

includes ITSOSSI3 in its cluster details.

Two members of four member cluster

ITSOSSI4

(8 GB Real Memory

ITSOLNX5 (6 GB)

ITSOSSI3

(30 GB Real Memory)

ITSOLNX5 (6 GB)

z196 z196

DIRMAINT

RACF

TCPIP

RSCS

VMPTK

Version 6.2

Dirmaint

RACF

TCPIP

RSCS

VMPTK

Version 6.2

DB2 v10

DB2 v10

ITSOLNX1-4 (20 GB)