DB6: How to deactivate file system caching in V9.5

July 3, 2009 at 6:30 am

[] [] [] [] [] [] [] [] [] [] []

Symptom
You want to deactivate file system buffered I/O on DB2 objects.
Other terms
file system caching, file system buffered I/O, dio, cio
Reason and Prerequisites
DB2 has own buffer pools in memory. When file system buffered I/O is used for table spaces, a page might be buffered on both DB2 buffer and OS file system buffer. Duplicate [...]

Use of Index Key Compression for Oracle Databases

July 3, 2009 at 12:38 am

[] [] [] [] [] [] [] [] []

Symptom
Database is using too much disk space for indexes
Other terms
disk space, performance, compression, disk I/O
Reason and Prerequisites
Index Key Compression is supported in SAP environments from Oracle Release 10.2 on.Index Key Compression is only available for B*Tree indexes and not for Bitmap Indexes.Please make sure that your PSAPTEMP Temporary Tablespace is at least as big [...]

Performance problem with MaxDB 7.7: High CPU system load

June 30, 2009 at 10:43 am

[] [] [] [] [] [] [] [] [] [] [] [] [] [] []

Symptom
After you update your SAP MaxDB instance to Version 7.7 or higher, the system performance is poor.
Problem identification:
a) You notice a high CPU usage (using operating system tools such as “sar”, “top” or “glance”). In particular, the CPU system part is high.
b) When you call more detailed information about the SAP MaxDB kernel [...]