In the past, Random Access Memory (RAM) was very expensive and admins were tightly constrained by budget and server slots when provisioning out infrastructure. Today's technologies, however, afford us very large capacity modules and sufficient slots to often provision as much as a terabyte (TB) or even more for each server.
Ceph components vary in their memory needs; in this section, we'll help you chose the right size for your servers to fulfill both operational and financial goals.
Consider the total RAM capacity of your servers. This is not nearly the quandary it once was, but it is still vital to plan carefully. If your server model accepts say at most 16 memory modules and your initial calculations are that 64 GB of RAM is what you need, resist the urge to save a few bucks on 4 GB DIMMs. Any future upgrades would require removing installed modules to make way for newer, larger DIMMs. Situations that could increase your RAM needs include:
- Adding more storage...