SAP HANA Fast-Restart

Thank you. Would it be possible to validate that? Two points come to mind:

• select table_name, is_preload, is_parital_preload from tables;
  Are all tables really set to preload=true?
• alter table <table_name> preload none;
  Create a script to change all BW tables to preload=false and then reboot the system again. What is the startup time then?

I would think that this information is very important for readers, because we are looking at two extremes.

Extreme #1 is all data preloaded in-memory.

Extreme #2 is an empty database that is loading data at access.

The reality will be somewhere in the middle. The main finance table/partitions for the current and previous year will be used from them get-go. The 20 years of historical data will not be used and if, rather by accident. These partitions might even be marked to be removed from memory after a certain amount of time without any access.

So at the end, all databases will have table/partitions constantly accessed versus table/partitions seldom used. Why wait for the seldom used tables to be loaded into memory during boot time if the data is not required?

Hence knowing the two extremes would help the reader (and myself) to quantify the situation. Currently people are saying a 2TB Hana takes 2hours to boot. Without any further qualifiers and footnotes. 

Appreciate your time!

-Werner