Tuning SQL Server 2005 on Windows Integrity Servers

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Test your Workload before you select Hyper-Threading
With the release of the Dual Core Itanium 2 processor (Montecito), each cell can contain 8 cores.
Furthermore, each core can be hyper-threaded, so the 8 cores might appear as 16 functional
processors to the OS and to the DBMS. HP Integrity servers are shipped with hyper-threading OFF.
Depending on the workload you run, turning hyper-threading ON can increase performance by 5-
10% but could also increase contention. You should test your particular workload with hyper-
threading before committing to its use.
Set Cell Local Memory to 100%
On cell-based servers, a portion of the memory in each cell can be configured as cell local memory
(CLM). CLM is non-interleaved memory that can be quickly accessed by processors residing on the
same cell as the memory. Processors in one cell can access memory in other cells, but local memory
access is always faster than remote memory access in cell-based Integrity servers.
HP nPartition management tools enable you to configure CLM for each cell either as a percentage of
the total memory in the cell, or as an absolute number of gigabytes of memory. When CLM is set to
100%, Windows and SQL Server minimize remote memory access. In moderate to heavily loaded
systems, especially doing OLTP, this can improve performance significantly.
To review CLM settings
Run the hpchkclm.exe utility from the HP Integrity Support Pack. The output report identifies the total
memory available and the memory allocations for each node:
C:\>hpchkclm
HP server: rx8620
Number of processors detected: 8
Processor architecture: ia64/itanium single-core
Perf. counter frequency: 1500MHz
Numa total memory available: 125GBytes
Node: Memory: Processors:
0 63GB 0, 1, 2, 3,
1 62GB 4, 5, 6, 7,
This system is configured for Cell-Local Memory mode. ÅÅÅÅ
Please refer to the HP Insight Management Agents
for more accurate results.
To set CLM parameters
Modify CLM settings for each nPartitition using the parmodify command.
Note: You must first install nPartition tools on the Integrity server (or on a remote management
station). See the “nPartition Guide” for detailed information about installing these tools.
Step 1. From the server console, run the parmodify command to change the
attributes of cells you wish to modify in each nPartition .For
example:
parmodify -p0 -m0::::100%
where: -p# = the partition number
-m# = the cell number in the partition
This example sets cell local memory to 100% for
partition 0, cell 0.
Step 2. For the changes to take effect, you must restart the server.