Multiple SAP instance on single physical server

[s0019996055]

Dear SAP expert,

Does anyone have any insights and/or experiences to share on installing and deploying multiple SAP instances on a single physical server host?

According the guidance of sapnote 1612283, Config number 3, we plan to migrate our SAP production landscape to new hardware.

The candidate new hardware is :

- 1 x DELL Power Edge R730xd

- Chasis with up to 24 - 2,5 inch hard disk

- 2 socket Intel CPU@8 cores

- LRDIMM DDR-4 16x32GB (512GB)

- 10 Gigabit NIC

The new environment would be like this:

- OS x64 MS Windows server 2008 R2 Enterprise

- DBMS x64 MS SQL Server 2012 Enterprise

- SAP Application Server ABAP - ERP 6.0 EHP 5

- Database size : 300GB (compressed)

- Provisioning tools - 70SWPM_SP05_08 and SAP KERNEL_721_EXT_X64

Disks-Array Configuration:

OS (rear)     : RAID 1 -  2x600GB 2,5" SAS 15K RPM

TEMPDB        : RAID 1 -  2x400GB 2,5" SAS SSD (8 files)

LOG           : RAID 1 -  2x400GB 2,5" SAS SSD (log+tmplog)

DATA1         : RAID 5 -  3x400GB 2,5" SAS SSD (2 files)

DATA2         : RAID 5 -  3x400GB 2,5" SAS SSD (2 files)

DATA3         : RAID 5 -  3x400GB 2,5" SAS SSD (2 files)

DATA4         : RAID 5 -  3x400GB 2,5" SAS SSD (2 files)

Distribution of Instance on this server (single physical host):

- DBMS - Database Instance (fixed min=max @256GB)

- ASCS - ABAP Central Service

- CI - Central Instance (PHYS_MEMSIZE=8GB,0 DIA)

- DI - 4 Dialog Instances (4xPHYS_MEMSIZE=16GB, 20 DIA)

Any information from anyone on here would be highly appreciated.

Thanks and regards,

Steve Handoyo.

[ACE-SAP · Accepted solution]

Hi Steve,

Are you planning to use virtualization and have you different SAP instances running on different VM  ?

If not there are no reason for having 5 instances with 4 AS running on the same physical server with only 18 cores.

A massive single instance should perform better (and will avoid buffer synchronization and multiple process overhead ).

Review the memory allocation, SAP is also able to make good usage of RAM, thus do not give most the of the RAM to the RDBMS, the rule is to give around 40% to SAP... and in your sizing you left 185Gb unallocated (or left for the OS)

Few other points,

- why not going on Win 2K12 R2 (mainstream support of 2K8 is over beginning of next year) ?

- Did you use quick sizer for choosing the target hardware ?

Regards

[s0019996055 · Accepted solution]

Hi Ives,

Thanks for the reply,

I am planning not using virtualization, all SAP instances and SQL server engine (DBMS) goes to single physical server.

Memory allocation like these:

- 256 GB or more for DBMS SQL server, to achieve minimal I/O

- 8 GB for SAP central instance, using profile parameter PHYS_MEMSIZE = 8GB

- 16 GB for each dialog instance (4 dialog instance), using profile parameter PHYS_MEMSIZE = 16GB

- 8 GB for OS

- unallocated memory (remaining) would be allocated to DBMS SQL server to achieve minimal I/O

Total CPU core with 2 socket @ 8 core with hyper threading feature would be 32 core.

What do you mean  "there are no reason for having 5 instances with 4 AS running on the same physical server with only 18 cores" ?

It is a good idea for using Win 2012 R2, thanks.

Thank you,

Steve

[ACE-SAP · Accepted solution]

Steve

One important thing is missing. How many concurrent users did connect on your production system today, how many workprocess did you setup and what are the maximum number of waiting request in the communication queue (SM51 / Goto / Information / Queue information) ?

If the user load can be handled by 50 workpocess then there are no needs to create multiple instances.

According to your Dell model you should have 2 E5 V3 CPU on the server, I would recommend the E5-2667 v3 .

Regards

[s0019996055 · Accepted solution]

Hi Ives,

Thanks again for the reply

Our current production system is:

- 150 concurrent user

- 1 central system (DB+CI)

- 4 Dialog instance (load balance)

There was 30 WP each dialog instance and 40 Max. No. of Request Wait in every Dialog Instance.

My question : Is it still no needs to create multiple dialog instance? if maximum number of waiting request around 40 in every instance?

I am considering using 2 socket E5-2667 v3 as you recommended, thanks.

Any information and recommendation from you would be highly appreciated.

Thank you,

Steve

[ACE-SAP · Accepted solution]

It is always difficult to compare concurrent users as they are rarely doing the same operations on SAP and requiring the same amount of power...

I've got a production system with 284 concurrent users, 495 modes that are able to work smoothly on a single instance with 20 DIA workprocess on a 4 socket 8 cores system (E5-4620).

You're DB access time should be good using SSD drive + big amount of memory...

That is why, even if your users are hard workers on heavy resource consuming modules I would try the single instance.

I do not think adding extra instances could help on a performance perspective.

It might only help to fully use all the available memory, with 512 GB and a 300 GB DB you could try to set the entire DB in memory

=> http://blogs.msdn.com/b/saponsqlserver/archive/2013/06/11/infrastructure-recommendations-for-sap-on-...

Also have a look to the MS tuning documents for 2K12

=> Performance Tuning Guidelines for Windows Server 2012 R2

Regards

[s0019996055 · Accepted solution]

Thanks for the information

Regards,

Steve

[giri_ayyagari]

Hi Steve

I don't see High Availability, can we asume it's VM environment ? if so is it FT enabled?  share more details.

-girir

[s0019996055]

Hi giri,

No VM environment and no HA.

Thanks,

Steve

[Sriram2009]

Hi Steve

Yes, you can install the Windows 2012 with MS Sql 2012 will support multiple SAP instance. For each SAP instance you can define the memory of 20 GB (Each SAP SID 14 GB + DB 6 GB (70% +30 %)) in database you can define the memory in MS Sql MMC 30GB

In our environment we have 5 SAP instance are connected one single DB in HA environment (Distributed environment) all our development & quality systems.

Regards

Sriram