SAP Basis Tech Supports

Symptom

You want to use an automatic check to check whether the configuration of your liveCache/MaxDB/OneDB (OLTP/BW) instance corresponds to the current SAP recommendations.

Other terms

liveCache, MaxDB, OneDB, BW, SAP Business Information Warehouse, parameter, configuration

Reason and Prerequisites

Reason:

Due to developments in experience and knowledge, it may be useful to adjust the liveCache/MaxDB/OneDB configuration. In this case, these are general configuration recommendations. In individual cases (depending on the load profile or the application profile), you do not have to follow these recommendations (for example, if you have been instructed otherwise by Support in relation to your system).

Prerequisites:

You use a liveCache/MaxDB/OneDB instance with Version 7.5 or higher and you want to check whether the configuration of your instance corresponds to the SAP configuration recommendations.
In general, the parameter recommendations that are described in the notes listed under “related Notes” are checked.

Note:

We recommend that you perform the check after each import of a new liveCache/MaxDB/OneDB version because different recommendations may be relevant for different versions. Since the configuration file that is attached to this note is regularly updated, you must download it before each check again.
Current check version: “1.15, May 28, 2009″

Additional information:

As of the liveCache/MaxDB/OneDB versions
7.6. Support Package 06 Build 03 (PTS 1160858)
7.7. Support Package 07 Build 05 (PTS 1160860)
7.8. Support Package 00 Build 11 (PTS 1160859)

the database analyzer that is included in the standard delivery analyzes whether the configuration of your instance was checked (if this is the case, the analyzer also determines when the check was performed and which version was used to do this). The system may issue the following or similar messages:
If a check has never been performed:
* W1 No configuration check of instance has been performed so far!If the check has not yet been performed for the current version:
*I Last configuration check of instance executed 2008-12-29 17:11:06 with checker version 1.08, December 29, 2008
*W1 Last configuration check based on version
7.6.06 Build 03, current version is 7.6.06 Build 04If the check has already been performed for the current version:
*I Last configuration check of instance executed 2008-12-29 17:11:06 with checker version 1.08, December 29, 2008
*I Last configuration check based on version
7.6.06 Build 04, current version is 7.6.06 Build 04Solution

The automatic check is performed using the Database Analyzer tool that already exists in your system. The check uses a special Database Analyzer configuration file.
The instance must have the status “online”.
Proceed as follows:
Download the SAR package that is attached to this note and unpack the Database Analyzer configuration file that is contained in the SAR package. The checks are implemented in this configuration file:
SAPCAR -xvf DbanalyzerParamCheck.sar
==> dbanalyzer_InstanceParameterCheck.cfgPerform the automatic check as SYSDBA (SUPERDBA) using the following command:
dbanalyzer -d -u
-f dbanalyzer_InstanceParameterCheck.cfg
-o -i -c 1 -t 1,1 [-n host]Analyze the screen output or the file
//DBAN.prt
Analyze all the outputs that are marked with “* W1 – *W3″.

Depending on the instance type and the MaxDB/liveCache/OneDB version that is to be checked, the following parameters are checked:
General parameters:
MAXLOCKS(MaxSQLLocks), _PACKET_SIZE(CommandBufferSize), _LOCKMANAGER_ENABLED,
_MAXTASK_STACK(MaxTaskStackSize), REQUEST_TIMEOUT(RequestTimeout),
ENABLE_SYSTEM_TRIGGERS(UseSystemTrigger)
SUPPRESS_CORE(AbortHandlingMode),
MINI_DUMP(MiniDumpType,AbortHandlingMode)I/O
_IOPROCS_FOR_READER, IOPROCS_SWITCH, USE_OPEN_DIRECT(UseFilesystemCacheForVolume), USE_OPEN_DIRECT_FOR_BACKUP(UseFilesystemCacheForBackup), SIMULATE_VECTORIO(UseVectorIOSimulation)
UseLobClusteringTasking/Dispatching:
LOAD_BALANCING_CHK(LoadBalancingCheckLevel), MAXCPU(MaxCPUs), XP_MP_RGN_LOOP/MP_RGN_LOOP(MaxExclusiveLockCollisionLoops)Optimizer:
HASHED_RESULTSET(UseHashedResultset), JOIN_OPERATOR_IMPLEMENTATION, LRU_FOR_SCAN(UseDataCacheScanOptimization),
_MBLOCK_STRAT_SIZE(InternalOrderStrategySize), MAX_HASHTABLE_MEMORY(HashJoinTotalMemorySize), MAX_SINGLE_HASHTABLE_SIZE(HashJoinSingleTableMemorySize), SHAREDSQL, OPTIMZE_FETCH_REVERSE, OPTIMIZE_FIRST_ROWS(EnableFirstRowAccessOptimization), OPTIMIZE_JOIN_PARALLEL_SERVERS(ParallelJoinServerTasks), OPTIMIZE_OPERATOR_JOIN, OPTIMIZE_QUERYREWRITE(EnableQueryRewrite), OPTIMIZE_STAR_JOIN, UPDATESTAT_SAMPLE_ALGO(UpdateStatSampleAlgorithm), OPTIMIZE_JOIN_OUTER(EnableOuterJoinOptimization),
OPTIMIZE_OPERATOR_JOIN_COSTFUNC,
OPTIM_CACHE(UseStrategyCache)
USESELECTFETCH(UseSelectFetchOptimization)Logging:
LOG_IO_QUEUE(LogQueueSize), LOG_MIRRORED, LOG_QUEUE_COUNT(LogQueues), LOCAL_REDO_LOG_BUFFER_SIZE(LocalRedoLogBufferSize)liveCache:
HEAP_CHECK_LEVEL(CheckAllocator), _MAXGARBAGE_COLL(GarbageCollectors), MAX_RETENTION_TIME(MaxRetentionTime), OMS_HEAP_COUNT(OmsSubHeaps), OMS_HEAP_LIMIT(OmsMaxHeapSize)

In addition, it is checked whether
defective indexes existthe database trace is activated.tables exist for which no statistics are stored in the file directory.logging is activated and the “automatic overwrite” is deactivated.the size of the data cache corresponds to our recommendations
(2% of the database size for Unicode, 1% for non-Unicode systems).