About performance hierarchy level 4
This section considers the population of the Dynamic Random Access Memory (DRAM) and the processor, specifically the number of cores should be populated in the system. Many people look to speed of the processor as the primary determinate of performance. However, backup and restore, particularly multiple operations of each are more reliant on the number of cores as each core can be performing a single or small number of operations.
DRAM population has a very close relationship to the amount of MSDP data to be addressed. The easy way to calculate how much RAM is required in the system is to allocate 1 Gigabyte of RAM for every 1 Tebibyte of MSDP data in the system. As an example, if creating a system that will have the non-appliance NetBackup maximum of 256TiB of MSDP storage, the system should have at minimum 256GB of RAM. The reason for this is the implementation of the SHA-2 HASH function as described in Chapter 3:
See Fingerprint lookup for deduplication.
If you are building a system with the 256 TiB of MSDP storage, it is a good idea to ramp up the RAM to 384 or 512GB to ensure no performance degradation when the storage starts to fill up with deduplicated data.
Lastly, the number of processor cores to allocate to the system is dependent on the type of backup jobs to be done. For instance, if concurrently backing up large number of VMware instances, then a larger number of cores is a good idea as there can be more concurrent jobs completed in a shorter time frame. On the other side, if backing up small number of large files the number of cores can be lower.
One method that is a good way to size your solution is, if building a higher performance system use the cost of approximately $1300.00 per processor. You can find this information at https://en.wikipedia.org/wiki/List_of_Intel_Xeon_processors. As an example, if we look at a current (as of the publishing of this document) list price there is a 24 core Xeon Gold 5318Y processor for $1283.00. Two of these would create a good solution with a total of 48 cores.
For mid-range systems, use the $700.00 mark. In this instance there is a Xeon Silver 4314 that has an MSRP of $694 and has 16 cores per processor. This solution would provide 32 cores, enough for the vast majority of systems, and able to accommodate tight budgets.