topic Re: How to project how much memory do I need to open a qvw? in QlikView

How to project how much memory do I need to open a qvw?

Mon, 26 Jan 2026 18:19:17 GMT

How do I know how much memory from the server takes to open a qvd or qvw? I realize that I'm a little bit tight of resources and I want to make a projection.

Thanks

Re: How to project how much memory do I need to open a qvw?

sibrulotte — Fri, 27 Dec 2013 21:18:43 GMT

A consultant showed me this, and If I'm not mistaking, I think it was 1.4 times the amount of ROM the file took, times the number of simultaneous users.

Let me check the web.

Re: How to project how much memory do I need to open a qvw?

paul_scotchford — Fri, 27 Dec 2013 21:24:59 GMT

Add around 10% memory consumption for every instance of the original document opened.

What is you server config ? What is the largest QVW that you have ?

Re: How to project how much memory do I need to open a qvw?

maxgro — Fri, 27 Dec 2013 21:26:37 GMT

Hi Pablo

you can find some help here

http://community.qlik.com/message/393976#393976

There is also the Qlikview Server Load Simulator.qvw to download at the sameplace

Regards

Re: How to project how much memory do I need to open a qvw?

Colin-Albert — Fri, 27 Dec 2013 22:30:55 GMT

Memory is not only consumed when opening a QVW, but is also used to cache expressions as users make selections within the app. If the server has free memory then the caching will improve performance as calculations can be retrieved from the cache rather than being recalculated. When memory resources are low, typically 70%, QlikView implements memory management to drop old cached expressions, this is normal. When the upper limit is reached (90%) then the memory management becomes more aggressive, which can impact on performance. So it is not simply a case of having sufficient memory to open all apps on the server.

Re: How to project how much memory do I need to open a qvw?

stevedark — Fri, 27 Dec 2013 23:31:39 GMT

Hi there,

The server will not directly load a QVD (though you will most likely have QVWs the create or consume these on the server). The size of a QVW on disk gives a good indication of how much memory it will take when loaded by the server. As well as a copy of the full QVW in memory each user connected to that document via the server will have their own cache - this is typically about 10% of the size of the document per user. As Colin points out, what the user is doing in the document (eg. what charts they are viewing and what selections they are making) will have a bearing on this.

QlikView Server is very good at managing it's memory - so it will just load items when it needs them and clears things down once no longer needed.

Hope that helps.

Steve

Re: How to project how much memory do I need to open a qvw?

Peter_Cammaert — Sat, 28 Dec 2013 12:00:01 GMT

A good (and fairly recent) explanation of memory and cpu usage by the QlikView Server is found in the QlikView Resource Library at www.qlik.com/us/explore/resources. The Technical Briefs section contains this useful document: QlikView Architecture And System Resource Usage In your case especially pages 6-9 provide valuable info

Best,

Peter

Re: How to project how much memory do I need to open a qvw?

Anonymous — Sat, 28 Dec 2013 13:14:17 GMT

Pablo

You say that you are 'a little bit tight of resources', what symptoms are you experiencing that brings you to that conclusion ?

Best Regards, Bill

Re: How to project how much memory do I need to open a qvw?

rwunderlich — Sat, 28 Dec 2013 19:42:12 GMT

Previous comments and the referenced technical brief suggest that the qvw size on disk can be used to estimate the RAM requirement. But it's guesswork (tech brief suggests 2x to 10x) if the qvw is compressed (default). There are three methods I can suggest to get accurate RAM requirements of the initial document open.

1. Save the QVW uncompressed (Document Properties, General, Compression, None). Then the QVW size on disk = RAM for open.

2. Generate memory statistics for the file (Document Properties, General, Memory Statistics button). Process the statistics with a QV app like QV Optimizer.

3. Use Document Analyzer (Downloads - Rob Wunderlich Qlikview Consulting) . The "Memory" sheet as discussed here Qlikview Notes: Identifying Unused Fields With DocumentAnalyzer will show how much RAM is required. It may also identify opportunities for RAM savings by dropping unused fields.

More about memory and disk compression here.

Qlikview Notes: Document Compression

-Rob

http://masterssummit.com

http://robwunderlich.com

Re: How to project how much memory do I need to open a qvw?

Mon, 30 Dec 2013 14:17:35 GMT

Thanks Simon

Re: How to project how much memory do I need to open a qvw?

Mon, 30 Dec 2013 14:29:46 GMT

Hi Paul

My server config is

Machine Information
		Computer Name	PVDW02
		Operating System Version	Win32_OperatingSystem=@ X64 (Microsoft Windows NT 6.1.7600.0)
		.NET Version	4.0.30319.1
		MDAC Version	6.1.7600.16385
		Monitors	1
		Physical Memory	32765Mb
		Available Memory	14438Mb
	CPU Information
		CPU 0	Intel(R) Xeon(R) CPU E5320 @ 1.86GHz
		CPU 1	Intel(R) Xeon(R) CPU E5320 @ 1.86GHz
		CPU 2	Intel(R) Xeon(R) CPU E5320 @ 1.86GHz
		CPU 3	Intel(R) Xeon(R) CPU E5320 @ 1.86GHz

and my largest qvw is 2.5 gb

Re: How to project how much memory do I need to open a qvw?

paul_scotchford — Mon, 30 Dec 2013 21:33:20 GMT

Hi Pablo

Running a single 2.5Gb qvw on this server will run ok, every instance that is opened by other users will require 10% growth of the original memory allocated by preloading the QVW.

I'm sure you have budget constraints, but this seems like a very small server (more a PC config) , but in any case if you plan to build and deploy more apps in QlikView (to a few or many users) you will need a decent sized server, this can only be calculated when you have a clear set of requirements e.g. Number of Doc licences required, number of apps to build and deploy, the ETL requirements from source systems (or Data Warehouse) will also need factoring in as processing of QVD's will require compute power and processing time (Usually overnight/early morn).

I'm not saying you need what we have (as I don't know your business) but we run a Win 2012 box, with 3/4 Terabyte of memory and 32 2.6 GHz cpu's, but we have a lot of users and some apps are 50+Gb in size.

Keep in touch, I'm happy to assist in your assessments as you grow your needs.

cheers

Paul