Sql processor affinity licensing

The bits corresponding to each CPU should be in one of these three states:. These settings are attempting to achieve the same result, and if the configurations are inconsistent, you may have unpredictable results.

As an example of setting the affinity mask option, if processors 1, 2, and 5 are selected as available with bits in positions 1, 2, and 5 set to 1 and bits 0, 3, 4, 6, and 7 set to 0, a hexadecimal value of 0x26 or the decimal equivalent of 38 must be used.

Number the bit positions from right to left.. The affinity mask option is an advanced option. Any operation running on a single NUMA node can only use buffer pages from that node. When an operation is run in parallel on CPUs from multiple nodes, memory can be used from any node involved.

Dynamic affinity is tightly constrained by CPU licensing. SQL Server doesn't allow any configuration of affinity mask options that violates the licensing policy. Skip to main content. This browser is no longer supported.

Download Microsoft Edge More info. Contents Exit focus mode. Is this page helpful? Please rate your experience Yes No. Use this page to view or modify your processor options.

Processor affinity settings are only enabled when more than one processor is installed. Assigns processors to specific threads to eliminating processor reloads and reduce thread migration across processors. For more information, see affinity mask Server Configuration Option. This setting is best for most systems. However, depending on your system configuration, setting this option to a specific value sometimes improves performance.

For more information, see Configure the max worker threads Server Configuration Option. Let me know if you can think of anything else to look into. Thank you. Ok, I suspect what you're seeing is not SQL not using the other processors, but a side effect of how affinity is set on higher processors. Check sys. That'll tell you if SQL is using those processors.

My disk throughput is only around 1. When looking at the load factor some are set to 0, 1, or 2. I'll run the query again when I have an active test going and observe. I'll post again if anything seems odd. Are you monitoring wait stats? Save my name, email, and website in this browser for the next time I comment.

Username or Email Address. Remember Me. Skip to content. Back to Overview. As you can see from the previous picture, there is now a Scheduler Affinity set: Scheduler 2 can now only run on CPU core 2 Scheduler 3 can now only run on CPU core 3 You can now test again this affinity by executing a CPU bound query, and running again the diagnostic query from previous.

If you have only enabled CPU core 2 and 3 on a 4 core system, you will get back now the value 4 or 8 — in binary or To be honest, this is not really the expected behaviour. Imagine you are running some application, and that application is performing CPU intensive work on core 2 or 3.

The result of this behaviour is that your SQL Server query will just take a longer time to finish its execution.