HA and memory consumption

[ujemvi]

Hi guys!

I have a problem with a FortiGate 600C. I'm currently using IPS, Web filtering, antivirus... you know, all the stuff. And, of course, I've reach to a point in which I'm having conserve mode events. My RAM memory is getting short.

I'm planning on buying a new FortiGate, and one of the scenarios I can approach is to buy another FortiGate 600C and make an active-active cluster. I've been told that the performance will raise with this.

Another option is to buy a bigger one and rearrange my network to use the two firewalls in order to keep using the old one.

One of my main concerns is the time that will pass before I'll have again conserve mode events. I don't want to be having memory problems in six months. I know that going for the bigger + AA cluster is the ideal solution, but that's money I won't have and I have to choose one of those two ways.

With the active-active cluster, I haven't found any info regarding RAM memory. Will it add like "4 GB + 4GB = 8 GB"? Or I'll get just a fraction of that?

Any ideas or experiences that may come useful please?