07-12-2012 11:38 AM
When building a server for use with Airwave, specific to processor sizing what is more beneficial when considering the Airwave applications specifically (VisualRF, SNMP Pollers, graphing/reporting engine, DB application, etc):
1) More Processor Cores
2) Faster Processor Speed in Mhz
3) More (multiple) physical processors
In reviewing the Airwave 7.3 Sizing Guide, some of the listed processors are no longer current or it is not most cost effective to purchase that processor model (i.e. cheaper current procs are readily available). There is also a mix of Core increase, Faster Procs or Multiple Procs as the number of monitored devices goes up. Clarification on benefits of cores, speed or count for processors would be greatly appreciated.
Also FYI: there is a typo in the 7.3 sizing guide - per the Intel processor spec website the W3670 proc is 6 cores, not 4.
07-13-2012 11:46 AM
Please reference the AirWave 7.4 sizing guide as it is the most current sizing guide available. That being said, we are working on a 7.5 sizing guide based upon next generation server hardware and cpu architecture. It should be available soon.
The priority for CPU sizing is as follows:
1) Processor Speed (Faster is better)
1a) Tasks are multithreaded, but faster CPU speed results in faster task completion and improves backend data handling as well as UI responsiveness
2) Multiple Physical CPU Cores (More is better) (Physical CPU cores i.e. a Quad Core CPU w/ HT = 4 physical cores and 8 total logical cores, Hyperthreading adds logical cores and some performance gains, but not as much as additional physical cores). The number of "physical" processors (i.e. 1 socket 8 core versus 2 socket 4 core each is equivalent) doesn't have much impact as long as the available cpu cores meets our recommendations
2a) Again, tasks are multithreaded and will take advantage of additional available cores (up to a reasonable number). This can be configured under AMP Setup.
3) RAM - The amount of memory is crucial to provide sufficient working memory space for processes. (More is better)
3a) It is highly recommended that you meet or exceed the recommended memory amounts
4) Cache size (More is better)
4a) affects CPU speed when processing tasks
As a side note, the planned next generation of CPUs we're going to be including in our appliances will be the Intel E5-2640 but you're welcome to spec faster/bigger CPUs.
If you have any additional questions or comments, please feel free to contact Aruba Support (firstname.lastname@example.org)
Sr. Network Systems Engineer - Service Provider Sales
Aruba, a Hewlett Packard Enterprise company.
07-13-2012 04:33 PM
Thanks for the follow up, much appreciated.
I am a little confused on one point however - In the Airwave Sizing Guides (7.4 and 7.5) all of the recommended CPU speeds are 3GHz or higher, and you indicate in your answer that Processor Speed is the top ranking criteria to consider. However, you noted at the bottom that Aruba will be using the Intel E5-2640 (15M Cache, 2.50 GHz, 6 Cores) in the next Airwave appliance...why would a slower than the recommended processor be slated for use in the next Airwave appliance?
Is there some point of diminishing returns on CPU speed being the top criteria, based on Aruba's choice to use a slower CPU with more cores in the appliance? Referencing the specs for the 1,000 AP level (Airwave Pro), the E5-2640 CPU is a full 1GHz slower than the recommended CPU speed for that number of APs.