New Java Node

[Former Member]

Hi Experts.

I have only one node, but I want to create a new node, I have understood that holds 2 GB of memory.

Is there a problem in the CPU or what would be the risk to create the node?

[sunny_pahuja2 · Accepted solution]

Hi,

You can add  new java node based upon below formula:

#ServerNodes = (AvailableMemory / N GB)

where N GB is the memory recommended per 1 server node in SAP note 723909.

Take care for No swapping and No paging.

Thanks

Sunny

[Former Member]

Angel,

As a rule of thumb, every Java insatnce should have at least two server nodes. Otherwise during a full GC, java instance halts until the GC finishes. That may hake several minutes. You do not want your production system showing hour glass for several minutes until the GC finishes. Therefore, add the second server node regardless. If a serious CPU strech occurs, you can always shutdown the second server node.

When you create the new server node, make sure that both of your server nodes have the identical parameters.

As far as the CPU utilization: Before adding the new server node, take a look at the CPU utilization using OS commands or Solution Manager and/or Wily (if you are using the latter two) . If there is a high CPU utilization you should find out what is causing that; system tools or applications and resolve those issues. If necessary have more CPU added to the server.

Before adding the second server node, keep a record of CPU utilization rates. After adding the new server node compare the new values with the old ones.

In addition to CPU considerations, you should focus on memory availability too. Make sure that the server has enough memory to fit the full Java instance into the physical memory.

Ref. OSS note: 723909

Neval

Edited by: Neval Ozturk on Mar 23, 2011 8:54 PM

[Former Member]

Hello,

creating a new server node means you have one more jlaunch process at your computer and so you could have twice the CPU load, especially at startup. During runtime all depends on the workload. So if your server now runs on low CPU load it should be no problem, if it is near the limit i would not add a new node.

Christian

[Former Member]

Hi,

The java stack is so "stable" that I always configure at least 2 server nodes.

If one JVM crashes, at least, I have still one server node still available.

If I have enough memory, and the system load will be high, I set up 3 server nodes.

Regards,

Olivier

[Former Member]

Well, that depends on the load that you are going to generate, but in general if you have sufficient memory, you can just add an additional server node to your java cluster.

Kind regards,

Mark