SAP HANA: The mysteries of Configuration and Parameterization

[former_member182913]

I am thinking about writing a Blog about SAP HANA configuration and database parameterization for a while, but I keep procrastinating... I  am as lazy as the SAP HANA table load process into main memory after a system restart...

Today (endlich!) I will introduce the topic, but I will try to keep it short. I'll leave the details for you to further test and experiment. If I feel like it, I may write some further episodes on this some other time.

The main challenge is the following: The topic is complex and not as sexy as, say, HTML5 based apps, the HANA XS Engine, Cloud or so.

However, those who learn the secrets and mysteries of database parameterization can move the world...

First I will describe the basics, and I will give you a small example:

• How and where to start? As first step you open your nice SAP HANA Studio
• You open the SAP HANA Administration console by double-clicking on your SAP HANA system on the Navigator panel, on the left side of the screen (both the Modeler or the Administration perspective in the SAP HANA Studio are OK).
• You will see the different tabs of the Administration Console, starting with an Overview Tab, continuing with the Tabs Landscape, Alerts, Performance, Volumes, Configuration, etc.
• You click on the Configuration Tab, et voilà, you will see the different configuration files, e.g. indexserver.ini, global.ini, statisticsserver.ini, and so on.
• If you open the corresponding tree for the different configuration files, you will see different configuration areas, according to relevant themes, e.g. under global.ini, you can see the area backup, memorymanager, persistence, etc. You can further drill down, and see the relevant parameters for the area in question.
• There is a very cute feature on top of the Configuration Tab: The Filter. There you can enter a search keyword in "natural" language, for example savepoint, and all parameters containing this keyword will show up! I am not saying that all parameters are self explanatory... They are definitely not. However, some of them are easy to use. You can start experimenting with the easiest and most transparent ones, first in a test system, mind you...
• Let's develop an example using the savepoint keyword:
  • After entering savepoint in the Filter field, you will see different hits containing this keyword. We will take the one under global.ini ==> persistence ==> savepoint_interval_s. This parameter is quite self explanatory and easy-to-use: It shows how often SAP HANA writes a savepoint on disk, in seconds.
  • The default value is displayed on the Default column on the right side of the parameter: On the current SAP HANA version, it is 300 s, that is, every 5 minutes, SAP HANA dumps all in-memory data to disk... With the most recent savepoint and the database log files, you can recover your SAP HANA system to the latest point in time.
  • Even though savepoints are written asynchronously, in order to optimize system performance, you may want to experiment with other values, different from 300 seconds... You only need to double-click on the Default value and enter your new value. That's it!
  • The Configuration screen will now show the new value for the savepoint parameter. It will also show a "diamond" symbol under the System column indicating that you have changed the parameter default... By the way, with SAP HANA 1.0 SPS4 configuration files (global.ini and co.) had to be backuped manually... This is planned to be changed in the future... I need to check if SPS5 already includes this feature...

That's it to start with.

You may want to further experiment with other parameters and keywords. Another cute example is the keyword password. Here you will find quite a few useful parameters that will help you define your password related security policies. The password parameters are often self-explanatory.

Have fun!

By the way, those who know me a bit by now may wonder where I left the Green, ecological touch in my blog today... There is definitely one:

I was just dreaming about a set of Green IT Parameters for SAP HANA... I still have to research a bit on that one...

Gemma Durany

Founder and Managing Director

WeeDooCare Business Solutions GmbH