Memory usage in Qv

[manoranjan_d]

1. How memory usage is calculated in QlikView

Options:

1. Number or pointers in QlikView memory use one bits for each pointer.
2. 2 bit can represent upto 4 values i.e. 2 to the power of 2.
3. To calculate memory usage in QV you have to calculate how much memory is required by the text values (bytes) and how much memory is required by the pointers(bits)
4. All of the above.

Pls let me know which one is correct and for the correct pls explain

[petter]

This is a good article to read for you I think:

Symbol Tables and Bit-Stuffed Pointers

[gsbeaton]

Hi Manoranjan,

There are a couple of spreadsheets and QlikView docs on the forum that will help give you an estimate, but there are so many variables that it will always be just a best estimate.

In general terms, you can split memory usage into 3 areas.

1. The size on disk of your application (the size of your loaded and saved QVW)
2. The cache size (as you make selections in your application, results are cached in memory for use later)
3. The session size (usually negligible, but worth factoring if your application has a lot of users)

To focus more specifically on your question.  Memory usage within your application depends on lots of factors.  I can't do better than insight puiblished by Rob Wunderlich over at Memory sizes for data types | Qlikview Cookbook where he discusses ram usage in much more detail.

Hope this helps

George

www.qliktastic.com