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?
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.
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.
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.
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.
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?
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.
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.
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.
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...