That's it:
The processes which are generating all this mess are:
- Microsoft.Exchange.Pop3.exe
- Store.exe
I'm referring to an MS Exchange Server 2010 - x64 (v.14.00.0722.000, Update Rollup 5 included), running on a MS Windows 2008 Server R2 Enterprise SP1 - x64. Both fully updated/patched, through the Windows Update.
The system who host them have 8GB RAM and an Intel quad core Xeon X5560 @ 2.8GHz CPU.
As you can see in the "Task Manager" screenshot above, the memory allocation value varies widely and continuously (practically in real time), from less than 6GB up to ~8GB.
Likewise, even the CPU usage is affected by this behavior and its value ranges between ~30 and ~50%.
Once again: the only processes who are involved in this, are those reported above (both Exchange related).
The Microsoft.Exchange.Pop3.exe process is the most "active", allocating and unloading RAM continuously, such as the "Private memory set" value varies from ~400MB up to 2,5GB in about 10 secs. And so on.
Same for the CPU usage by this process, that varies from 25% up to ~40%. Steadily.
This is a constant behavior, at any time of day (or night). So I guess no scheduled or "real-time" processes/services (e.g. antivirus) should be involved.
Conversely, the Store.exe process behavior is quite normal, holding about 3GB of "private set memory" and taking few % CPU (about 2%) just for a while, every ~30 secs. I've already read in some discussion that Store.exe tends to allocate a lot of memory (according
the free memory available on the system) for better performance. So, may be ok.
Summing: to be honest, I don't know if these are normal behavior or not. But, referring to the Microsoft.Exchange.Pop3.exeone,it seems quite strange to me.
Feel free to ask me more details that will help you to understand my question or the problem.
Thank you in advance for your time and your valuable support.
Daniel.