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Nmon is a tuner and benchmark tool on Linux. Capture disk, cpu, memory , filesystem, resource usage, virtual memory
As a DB2 DBA it's a very effective method of capturing different types of in data in one interface.
nmon is useful ...
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To display network connections and various network interface statistics – netstat is a handy command – line based tool.
Why is it useful for the DBA ?
Execute netstat –an to view all active connections (TCP and UDP ports) on a server. The DBA has a quick overview of networ......
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Common reasons for query time-outs are :
1) The application starts using a query not optimal for the index
2) Hardware changes\ Configuration changes
3) Increased load
If you suspect the query time-out is due to memory issue , continue reading.
Debugging a query-timeout is tricky. I......
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This post discusses SORTHEAP DB2 and pinned pages Information message in db2diag.log
FUNCTION: DB2 UDB, buffer pool services, sqlbKeepPagesPinned, probe:20
MESSAGE
: ADM6071I The maximum number of pinned pages allowed concurrently was
reached in buffer pool "MYBUF8K" (ID "2"). As a r......
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A useful command for DB2 DBAs is the LIST UTILITIES command.
It displays the list of active utilities.
Examples of usage include : BACKUPS, RESTORES, performance issue, progress of RUNSTATS
[db2usr1@server1 ~]$ db2 list utilities show detail
ID = 36708
Type ......
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A neat test for read speed backup throughput is to use the Backup to NUL .
NUL is a special “file”. It's as a nul device , anything “written” to it is discarded.Don’t confuse with the SQL reserved word NULL.
Before you run this statement , note that even as the file is not going anywhere , SQL Se......
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Question: I’ve just been handed a new Linux Server build, on a new storage system. The RAID levels are different and the storage parameters have changed. I need to measure the IO performance of the new system and compare to the current system.
DB2 will be deployed on these servers, which are ver......
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Use the script below to rebuild an index on a table
ALTER INDEX MY_INDEX_NAME on MY_TABLE_NAME REBUILD;
Check SQL Server BOL for a the full list of options
Notes
1) Issuing an Index Rebuild request, drops and recreates the index
2) If rebuilding a CLUSTERED INDEX, nonclustered index......
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Part of the Performance Tuning series – Performance Stack, this section looks at Access Path Tuning. How does the user access the data and how can the access be maintained. The purpose of the series is a general approach to Performance Tuning – independent of database server platform. A large ......
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Fragmentation of an index can severely affect performance. When logical ordering of the key within a page does not match the physical ordering within the data file, fragmentation exists.
I execute index maintenance scripts for databases on a regular basis. If I’m executing a custom job, such as ......
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