Memory Parameters used for Cluster System

[Former Member]

My PRD system is in cluster. Serv A has 8 GB of RAM and Serv B has 8 GB of RAM.

The serv A is the aplication and the serv B is the data base.

Today if one serv fails the other take the lead.

We are going to incresse system memory in both server to 20 GB.

My question is , Should i have to configure the aplication and data base to use ALL memory available ?

Or i need to use just half of memory because if one sever fails, it will use more memory for aplication or database.

Today PHYS_MEMSIZE = 4527.

Thanks

[Former Member · Accepted solution]

this needs a sound knowledge of cluster enviroment as well as from operating system knowledge.

May be you can correct information from Database forum

Expert Forums » Database & OS Platforms » SAP on SQL Server

http://www.databasejournal.com/

All the best

nag

[Former Member]

Ok, let try explain.. Sorry about my bad English, I am from Brasil..

My cluster system was before configured to "max performance"...

So the server A and server B was cofigured to use all memory available.

Server A was set in Cluster Administration to just handle SAP aplication server, the server has 8 GB of ram and was set in SAP parameters to use 8 GB of ram

Server B was set in Cluster Administration to just handles Data Base, the server has 8GB of ram and was set in SQL to use 8 GB of ram.

What happens is if one system fails is the other one can't handle the SAP aplication and data base on to just one server because it will be 8+8 GB of ram in just one server. So the system didn't get up.Rememer that we did this because was asked to us "max performance at all cost "

This was before, now it's diferent, If one system fails the other take the lead with no problems.

SAP aplication server and Data Base can be run in just one server with no problem.

But the problem is i didn't see how it was configured,,, Wich parameters was used to Cluster system works that way..

So now i going to incrise more memory and i want to configured this parameters right..

I need to set my system to use the additional memory availble and still has the option to run SAP aplication server and Data Base in one server.

Please guys help me to do a great job...

Like a said before i will use Win 2003 x64 + SQL 2005 ECC 5.0 to use 20 GB or RAM.

Thanks a lot.

[Former Member]

My PRD system is in cluster. Serv A has 8 GB of RAM and Serv B has 8 GB of RAM.
The serv A is the aplication and the serv B is the data base.
Today if one serv fails the other take the lead.

May be I am not clear what you are trying to achive but Server A and Server B are both App/DB servers or not. In my view app should failover on inactive app server and same for the DB. Ideally active/inactive servers should have same configruation.

[Former Member]

Yes, this should be the scenario in cluster environment.

may be the question needs to be little bit clear.

Regards

nag

[Former Member]

Sorry,

I forgot to tell my system config :

Win 2003 x64 + SQL 2005

So if my both server has 20 GB of RAM the parameters should be :

SAP = (physmem_size = 12 GB)

SQL = (min and max_server_mb = 8GB)

My question is, How to configure this parameters with both servers ?

Today I let my server A with the aplication and my server B with the data base.

If one server fails, the aplicantion and data base goes just to one server, it's working this way today.

I am afraid if one server fails, the server that is on, can't handle aplication and data base at same time due wrong parameters.

Thanks guys for help me.

[Former Member]

SAP Note No. 327494 Configuration Parameters for SQL Server 2000

SAP Note No. 112266 SAP and MS Cluster Server: Frequent questions and

SAP Note No. 879941 Configuration Parameters for SQL Server 2005

You can use SAP Note 327494 for parameter related query:

For your system Point 6 will be applicable.

6) When SQL Server 2000 coexists as a combined system with either a

Central Instance or an Update Instance Application Server

and there is > 16GB of physical memory,

the following is proposed:

{Windows 2000 should be Datacenter}

SAP AS Memory should be fixed by PHYS_MEMSIZE to 30% of (total

physical memory - 1 GB)

<minMB> = <maxMB> = 30% of (physical main memory - 1 GB)

{1 additional GB should be left for OS management of more AWE}

<minMB> and <maxMB> must be less than 16GB

{this is because the /3GB switch is required by the CI or

Application Server}

<setWS> = 0

<awe> = 1

For Windows related memory settings please follow the SAP Note SAP Note No. 88416 Zero administration memory management as of 4.0A/

So please do the settings as per the SAP Notes and do let me know incase any confusion.

Thank you,

Tilak

[Former Member]

pls go through the below tags and also make sure High avilability cluster/HACMP systems

depends on operating system scalably.

http://www.saptechies.com/sap-system-under-microsoft-cluster-server-mscs/

http://help.sap.com/saphelp_nw70/helpdata/en/08/5743714ae611d1894f0000e829fbbd/content.htm

http://help.sap.com/saphelp_nw70/helpdata/en/43/39c7b227b91bcbe10000000a1553f7/frameset.htm

for AIX systems you can all information from AIX propritery site

http://rootvg.net/

regards

nag

[Former Member]

Hi,

The memory distribution for Apps and DB depends on the OS and database(with version) you are using.

Windows + SQL -- 60% of physical memory to Apps (physmem_size:ZAMM)

40% of memory to DB (min and max_server_mb)

Windows/Unix + Oracle --- 70% to SAP Appl memory

30% to Database

You should configure these parameters equally in both of the servers, so that in failover it wont create any problem.

Please let me know incase any doubt.

tilak