APM and ASM memory usage for sizing a box

I just checked three different BIG-IP systems that I work with, and they all showed the same value for minimum memory required to run the various modules (for example, 808MB for ASM) but the actual memory allocation was slightly different for each BIG-IP. Based on this, it appears that memory is allocated based on what is available on the system.

That said, I'm not sure if the memory gets allocated when the module is provisioned and stays at that level (based on the available memory of the system at the time), or if it changes as needed even if you don't make any module provisioning changes. I guess you could note the memory allocation in the GUI (System >> Resource Provisioning) and then check back periodically to see if anything changed.

I hope this helps!

Thanks John. I have done some more research since then. You are right, if the allocation method is "nominal" the allocation depends on the total available memory.

I've been told by a trusted source: It appears the value shown on the resource manager is what is required to run the base functionality of the module. Memory is then dynamically allocated from outside the allocation for various features (ie XML schema checks).

Anyway I am chasing up our local F5 SE to confirm one way or another.

I actually have a related question rather than an answer to yours. Is it normal and expected that actual memory usage by ASM will steadily increase as ASM is enabled for more VS's? I have a somewhat unique environment in that I have a large number of VS's, each for unique customers, but the same web application behind each (well, same webapp code in front of unique customer databases). So while I have only one policy I have hundred's of VS's that I am/will be applying this policy to. Do you know John if there is any known formula for calculating total ASM memory usage based on the number of VS' for which it is deployed? Thank you.

I actually have a related question rather than an answer to yours. Is it normal and expected that actual memory usage by ASM will steadily increase as ASM is enabled for more VS's? I have a somewhat unique environment in that I have a large number of VS's, each for unique customers, but the same web application behind each (well, same webapp code in front of unique customer databases). So while I have only one policy I have hundred's of VS's that I am/will be applying this policy to. Do you know John if there is any known formula for calculating total ASM memory usage based on the number of VS' for which it is deployed? Thank you.