topic Re: QlikView Desktop - slow over Network in QlikView

QlikView Desktop - slow over Network

shane_spencer — Sat, 16 Nov 2024 20:18:09 GMT

We use QlikView Desktop for our Apps (not server). We host the Apps on a LAN in London. The guys in the London office have quick response, we in Leeds have really slow responses. For example it takes them 6 seconds to open a 900Kb (that is kilobytes not megabytes) and it takes us 3 1/2 minutes. However if I reduce the number of sheets in the qvw from 20 down to 1 it reduces the time it takes to load dramatically even though the size remains more or less the same. It does not take 3 1/2 minutes to open other file types over the LAN.

Also navigating through an Document opened from the LAN compared to one opened from my C drive is very slow. This is suggesting that the Document even once opened is constantly reading/writing to the Network.

Does anyone know anything about what's going on? Yes I understand the Network is slow but why does it affect QlikView so badly? Why is QlikView so slow even after it is opened?

Re: QlikView Desktop - slow over Network

Daniele_Purrone — Thu, 08 Aug 2019 11:08:35 GMT

Hi! QlikView doesn't handle the smb connections to the shared file, that's done completely on Windows side. So, any slowness in that area comes from the environment.
QlikView doesn't write over the file, if you don't save it. If there's any action on that side, is done by either Windows or some third party tool (for instance antivirus).
You might indeed some antivirus software scanning data as it comes via the network, and slowing down the loading of the file.

Re: QlikView Desktop - slow over Network

shane_spencer — Thu, 08 Aug 2019 12:19:01 GMT

So once a file is opened is the smb connnection kept open? I'm just wondering why the Documents are so slow even after opening? For example if the Network is slow then an Excel document is slow to open, but once it's open it's then just as fast as if it was a local document. Is it because QlikView documents are "shared"?

I'm working with our Network team to resolve the issue but it may help to understand why QlikView is so adversely affected.

Re: QlikView Desktop - slow over Network

Daniele_Purrone — Thu, 08 Aug 2019 13:33:21 GMT

The connection does not stay open. You can easily verify that by opening any qlikview document (either local ones or network ones) and deleting the actual file while it is loaded into the client. You'll be able to delete it (it's not locked) and it won't be created again until you save it again.
I'm surprised that documents are slow after they have been loaded into memory, I still suspect it might be some security software having stricter checks on in-memory files that have been loaded via network. But I'm only guessing.

Re: QlikView Desktop - slow over Network

shane_spencer — Thu, 08 Aug 2019 13:36:47 GMT

Thank you Daniele. I'm really struggling to understand why they are slow, as it goes against my understanding of QlikView, but I'm hoping the Network team can resolve the issue. It just seems really strange, and I wouldn't believe it if I didn't see it myself.

Re: QlikView Desktop - slow over Network

Brett_Bleess — Tue, 27 Aug 2019 12:35:31 GMT

Shane, just wanted to follow-up on this one to see if you figured anything out, as this would be a good one for others to know if you did, as like you, I am puzzled as to why things are so slow here, as my coworker is correct in that once the QVW has been opened by the client, we no longer need access to the QVW file in most cases as he noted, but I am wondering if there is something you have in the app that is doing something. About the best I have as well is something scanning things as the transfer of the file contents is occurring, but once the file is transferred, the calculations should only be occurring on the active sheet as well, not all the sheets, so I am at a bit of a loss on the sheet related piece as well. Sorry I do not have something better here, but if you did get any further info, feel free to post, and I might be able to come up with something further at that point.

One point of clarification as well, you are doing a File\Open not a File\Open in Server, correct?

Regards,
Brett

Re: QlikView Desktop - slow over Network

shane_spencer — Tue, 27 Aug 2019 13:28:01 GMT

Hi Brett - I didn't get to the bottom of this. The Network guys have found some issues as to why the Network was so slow, but it did not explain why navigation in QV etc would be so badly affected. It must be some weird quirk of QlikView Desktop. We are not using Server or Open in Server. These are all desktop tools we use. Some with no actual data in, but are used as an access point so just a load of buttons. When we open a locally version it's fine, but if we open one from the Network it's prohibitively slow, even hanging on basic navigation or changing of variables - things that in theory are not reading/writing to disk.

Re: QlikView Desktop - slow over Network

Brett_Bleess — Tue, 27 Aug 2019 13:41:57 GMT

Shane, you using the OnOpen trigger in any of the apps? If so, what is it doing? Weird thing still is why locally things are fine v running over the network though, but that is the best of which I can think that might be in play from our side of things.

Regards,
Brett

Re: QlikView Desktop - slow over Network

shane_spencer — Tue, 27 Aug 2019 13:46:43 GMT

Hi - yes we use the On Open Trigger from a number of things from resetting variables, setting zoom and reloading data. But that would only explain why opening is slow, not the Documents themselves.

Re: QlikView Desktop - slow over Network

Brett_Bleess — Tue, 27 Aug 2019 13:49:57 GMT

Just remember if you use the Edit Module/Macros, that is going to force a single-thread calc condition across the board while that is running... You may want to try a version of the app where you take those out etc. and see what happens in that case...

Regards,
Brett

Re: QlikView Desktop - slow over Network

shane_spencer — Thu, 29 Aug 2019 10:22:43 GMT

as a test I removed all on open triggers.

266kb file took 1 mins 27 secs to open with triggers. same file took 1 min to open without triggers.

The same file opened locally takes about 4 seconds.

The network is not that slow. For example I can copy/paste in a few seconds. So it's something in the way the QlikView communicates with the Disk.

I did previous tests and if I remember correctly the thing that had the biggest impact on opening speed was the number of sheets in a qvw.

Re: QlikView Desktop - slow over Network

Brett_Bleess — Tue, 03 Sep 2019 13:25:27 GMT

Hey Shane, if you are current on maintenance, I think I would recommend you go ahead and open a support case at this point, if you can attach one of the qvw files that is giving you trouble, we can have a closer look at things to see if we can spot something to give you a better idea of where things may be. Obviously the OnOpen has an impact, but it does not explain everything unfortunately... If you do open a case, feel free to send me a private message via Community here with the case number, that way I can go have a look at things...

Cheers,
Brett

Re: QlikView Desktop - slow over Network

marcus_sommer — Wed, 04 Sep 2019 07:48:46 GMT

Yes, it sounds weird but I think there are a lot of possibilities which might cause such strange issue.

At first I would also think on any security tools / policies which may had identified the application as a network/internet file (similar to the way Windows handled files which are downloaded from the internet or from outlook) and now a heuristic routine checked every change in the RAM or the interactions with the OS and/or QlikView runs then in a kind of a sandbox or something similar. Normally your IT should be able to shed light in way they had implemented their security. A check without further information is surely not easy but I could imagine that by a close monitoring of the processes in the task/resourcen/performance manager and the various log-files should give some hints what's happening (in beforehand switch off everything what's possible, various auto-starts, print-driver and so on to reduce the amount of data).

On the Qlik side I suggest to check if there are prj-folders for those applications. Also does shared-files exists - even if you used the qvw's only with the desktop client the may exists (if there is or was any server usage of them) and also contain server-objects or maybe even extensions. Further a look on the used releases of QlikView may be helpful because it might results in any incompatibility.

Another thought goes to data and expressions in the application itself. Are there any document-related functions in use, like documentpath() or the direct discovery feature. Further is there any section access in use. All of them may not completely work and leading to invalid expressions or calculations over loosen tables or similar.

Further were there any changes within the easter egg like enabling the extended logging or macro-functions? In general it would be useful to check the user-properties to various settings, like the various paths, auto-saving, mail-settings (any alerts enabled?) and so on ...

Some of the above mentioned things seems to be quite unlikely but I would exclude them one after another - just to be sure. Good luck.

- Marcus

Re: QlikView Desktop - slow over Network

shane_spencer — Mon, 09 Sep 2019 09:47:54 GMT

After some testing we've identified the issue as being text boxes linking to 7 icons and 1 logo - all png's totaling about 75kb in size. Working from home (not in office) it took 7 minutes to open a 1.5Mb qvw; then the same qvw but the images replaced with webdings, windings and plain text took 15 seconds to open.

No idea why the big difference in performance but at least getting closer to what specifically in out qvw's is slow.

Re: QlikView Desktop - slow over Network

marcus_sommer — Mon, 09 Sep 2019 13:32:15 GMT

How are the png-pictures implemented - as image within the textbox or as background-image?

AFAIK is it implemented as background-image the picture will be embedded within the qvw and is it an image in the textbox it just stored the path to the file and pulled it by each opening and if the path is an expression or a variable the pulling of the image might be triggered more often. Is the last the case then it's probably not the file-size which caused the delay else the number of calls and from a security tool point of view it might look that an application is loading code from a public network and scanned it each time.

- Marcus

Re: QlikView Desktop - slow over Network

shane_spencer — Mon, 09 Sep 2019 13:54:57 GMT

They're as text boxes. Embedded are no good because they will not resize. Thanks for the info. Will feed it back to our Network guys.

Re: QlikView Desktop - slow over Network

marcus_sommer — Mon, 09 Sep 2019 14:35:34 GMT

I'm not sure if my last answer was clear enough - with background-image I mean a background-image in the textbox and not in the sheet. AFAIK you could position and resize them (respectivelly the textbox) like the picture is shown in the content-area of the textbox.

- Marcus

Re: QlikView Desktop - slow over Network

shane_spencer — Tue, 10 Sep 2019 08:39:23 GMT

I might test this but if memory serves me correctly they didn't resize well to different screen resolutions. Or perhaps the resolution of the image because blurry. But the biggest disadvantage is that we change the "logo.png" to be specific to a client, so if it's an external file it's as simple as replacing the png if it's embedded it's a lot of work as we have a suite of Apps not just 1 qvw.

Re: QlikView Desktop - slow over Network

marcus_sommer — Tue, 10 Sep 2019 09:07:47 GMT

I'm not absolutely sure but I believe there is no essential difference in sizing and resolution between both ways to display pictures.

Beside this I assume that your way to provide the path is a combination of fixed text and one or more variables which change their value depending on the documentname() or something similar. I never really test it (it's probably quite difficult) but I could imagine that the variable and/or the expressions within it trigger the path-evaluation quite often and may therefore delay everything quite significantly (in a not suitable environment).

Depending on your requirements it might be just solved with multiple textboxes - each one with it's own picture - and then the visibility of the textbox is controlled with your logic. If there are more strict restrictions the visibility might be also controlled through a section access (I assume there is already one to restrict the data within the application).

A further option could be to load the pictures into the qvw: Loading-Images-into-QlikView.

- Marcus

Re: QlikView Desktop - slow over Network

shane_spencer — Tue, 10 Sep 2019 14:51:12 GMT

Actually it's much simpler than that. We have a path:

..\..\SYS\_Images\logo.png

and when we roll-out our tool to a new client we replace the logo.png hence customising all qvw's by one simple action.