Requirements are here:
Minimum and Recommended Hardware Requirements (softwareag.com)
You’ll see it recommends 2 Cores, and 2GB of RAM minimum.
It’s hard to confirm your use-case exactly, this depends on the size of the messages/etc. Typically, UM is more io bound than CPU, so network and disk speeds can often be limiting factors. I’d suggest 2 Cores and 6GB of RAM would be a good starting point, but something that you might have to increase, especially if the average messages sizes are quite large.
Another challenge you might face is at 85 messages per second, if the subscribers are slow, you could face a growing backlog of messages, so you’ll need to ensure enough storage space to hold them, and have enough ‘quiet’ time to get through the backlog, or work on improving the subscriber speed through scaling out, optimization, etc.
You really don’t want the storage to fill as that would bring down the UM server.
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