HP IO Accelerator for BladeSystem c-Class Podręcznik Użytkownika Pobierz pdf (Strona 11)

Architectural scenarios 11

Architectural scenarios

Scenario 1: The entire database fits on the IO

Accelerators

1. Place the data files on one IO Accelerator.

NOTE: You can use one IO Accelerator or a RAID 0 set of multiple IO Accelerators.

2. Place the tempdb file for both data files and log files, the log files, and backup files on another IO

Accelerator.

3. If available, give the tempdb file its own dedicated IO Accelerator.

Scenario 2: The database is too big to fit on the IO

Accelerators

1. If the database is too large to fit the entire database on the IO Accelerators, then place specific

database elements that use the most I/O resources on the IO Accelerators.

2. Query the sysprocesses system table. If the waitresource file appears as 2:1:1 (PFS Page)

or 2:1:3 (SGAM Page), then you can successfully move the tempdb file to the IO Accelerator.

tempdb considerations

The following SQL operations require high performance from the tempdb file:

• Repeated create and drop of temporary tables (local or global).

• Table variables that use the tempdb file for storage purposes.

• Work tables associated with CURSORS.

• Work tables associated with an ORDER BY clause.

• Work tables associated with an GROUP BY clause.

• Work files associated with HASH PLANS.

For optimal tempdb file performance, use these guidelines:

• Dedicate a separate IO Accelerator to the tempdb file.

• Create multiple tempdb data files. The number of files must be equal to the CPU cores (not

hyperthreaded). For example, two Quad Core CPUs must use eight data files, even if the CPUs are

hyperthreaded.

• You must have only one tempdb log file.

1 2 ... 6 7 8 9 10 11 12 13 14

Brak uwag

HP IO Accelerator for BladeSystem c-Class Podręcznik Użytkownika Strona 11