Why use more than one node

[concord]

If a system is hosted on a single server is there any reason to run more than one node?

I've been running a singleUser app server for ever, unless I wanted to spread load onto another server I see very little reason in using JadeRAP at all.

Thoughts?

[ghosttie]

Having a database server would allow you to use jadload etc. in multi-user mode

[BeeJay]

If you have no reason for running a JadRap, such as multi-user utilities etc, then there is little or no benefit for you in running a JadRap process. If you need to run things like SDS or RPS, then I think you have to run a JadRap currently for that to work. Also, if you want to use the fat client ODBC driver for user queries then you also need a JadRap process for them to connect to. Other than that, assuming you don't need to spread your users across multiple nodes, for a very large number of concurrent users, you'll probably never need to use a JadRap process.

Cheers,
BeeJay.

[allistar]

An issue with running a single user app server is that you won't be able to isolate the caches of various clients. E.g. if you have clients that require large images you would normally put them in a separate app server so it doesn't fill or spill the transient cache for other users. Using multiple app servers is also a good way to improve security between users and support/developers (via [JadeAppServer] EnableAppRestrictions). E.g. users connect to the main app server which has the apps locked down, support and dev connect to a support a different app server and access to this is controlled via firewall rules.

I would expect a single user app server to perform considerably better as there's fewer hops from disk to node, and locking semantics are most likely modified.

[concord]

Thanks for the feedback.

We switched JadeRAP off about 15 years ago! Back then there certainly was a noticeable performance boost.

[Ty]

I'll just chime in with some reasons that haven't been mentioned.

The database server is 64-bit only. You may have a 32-bit .Net or ActiveX component for which there is no 64-bit equivalent. Thus, you require a 32-bit app server.

Another reason you might choose to run app servers is system resilience. You may encounter a bug, either in 3rd party software, or, heaven forfend JADE, which takes your app server down. Then you have two problems, one, reading your multi-terabyte database back into memory, and two, all your users have been kicked.

Performance isn't generally seen as a driving factor in the decision.