Upgraded our FAZ-VM to v6.2.3 this morning. Am getting high 40%+ CPU usage on the VM. "exec top" shows this is caused by /bin/clusterd. From reading another thread here, it was suggested that this is a known problem in v6.2.3 and maybe there is an updated/customised build of v6.2.3 which fixes/patches around this. I have opened a ticket with Fortinet and will post again once I get clarification and/or a fix.
Yes, this sounds like bug id 0596252. There is indeed a special branch which contains the fix related to clusterd. You must open a support ticket (as you have done) in order to be provided the image file. Fix will be in 6.2.4 when it is released.
UPDATE -- because Fortinet Support advised that v6.2.4 would not likely be available until end of April, I obtained a temporary firmware build 1248 from them and deployed this to our Fortianalyzer late last week; CPU is now back to normal and as best I can tell everything else is still working fine.