LDD - Extremely slow loading model

[GoldVillage]

I have been working on a project for 2 1/2 years and it has ofcourse been alot of re-dones and savings over and over old files, but i have kept the entire build in different modules and sections and everything has just became slower and slower, as soon as i import several modules and start putting the model together... it takes MINUTES to loading up.

The entire model as it is right now is approx 2400 pieces in ldd, but even the smallest modules/sections of like 100-200 pieces takes many seconds to load (this wasnt the case before) 

Is there a way to fix this lag or has the files somehow just gone bad over the years? 

Im using a G4560 with 8gb ram, and the drives are SSD so it shouldnt be any problems, atleast it wasnt that before.

Edited June 10, 2018 by GoldVillage

[NathanR]

If you start a brand new file and build a 100-200 piece model from scratch (not importing anything), does the file still take minutes to load?

I have found that for large models (>5000 parts), a lot of editing will cause a slight delay in load time. But at worst this has only ever been a few seconds for me. I assume that the LDD xml file can get a little messed up with too much editing, and a complete rebuild is needed to fix it.

[sed6]

By modules and sections do you mean groups? If so you can try saving each group as a template (ctrl-alt-g), then starting a brand new file and importing each template. Perhaps that will clean up the .xml file? Maybe you can even verify that idea by looking at the file size of your current model and comparing it to the file size of the new file. Let us know how it goes. 

[SylvainLS]

An LXF file isn’t a Word™ file   It doesn’t get “messed up” with time.  The information is pretty straightforward: parts, their positions, colours, decors, their connections, the hinges, the groups.  There’s no history or timeline or temporary data in there.  It’s clean.

What’s making LDD slow down is the number of bricks and colours and, especially, decors, you have viewed (not necessarily used: browsing is sufficient).  It fills up the memory, and LDD is 32bits, so its memory usage is limited.

[GoldVillage]

29 minutes ago, NathanR said:

If you start a brand new file and build a 100-200 piece model from scratch (not importing anything), does the file still take minutes to load?

I have found that for large models (>5000 parts), a lot of editing will cause a slight delay in load time. But at worst this has only ever been a few seconds for me. I assume that the LDD xml file can get a little messed up with too much editing, and a complete rebuild is needed to fix it.

A new build from scratch wont cause any delay, i wont to a total rebuild because it will take like forever and who knows... maybe the same problem will occur again :/

[GoldVillage]

39 minutes ago, sed6 said:

By modules and sections do you mean groups? If so you can try saving each group as a template (ctrl-alt-g), then starting a brand new file and importing each template. Perhaps that will clean up the .xml file? Maybe you can even verify that idea by looking at the file size of your current model and comparing it to the file size of the new file. Let us know how it goes. 

With different modules i meant the model is saved in modules... like front and a rear section, axles, cab, hood etc. I saved all those individualy instead of building everything in just one file.  The build is 205 kb so far and takes 2+ min to load, in a comparison the L350 lxf file i have is 160 kb and it takes just 7 sec to load...

Edited June 10, 2018 by GoldVillage

[sed6]

I think I understand. So with each module being a seperate file have you imported each module into a single large file and saved it? Is that what's running slow? In my experience a large file created by importing many smaller files can run slow. That was a large 5-6k piece file created by a half dozen or so smaller files. I still think creating a new file and pasting in templates as opposed to importing files could be the solution. 

[GoldVillage]

1 hour ago, SylvainLS said:

An LXF file isn’t a Word™ file   It doesn’t get “messed up” with time.  The information is pretty straightforward: parts, their positions, colours, decors, their connections, the hinges, the groups.  There’s no history or timeline or temporary data in there.  It’s clean.

What’s making LDD slow down is the number of bricks and colours and, especially, decors, you have viewed (not necessarily used: browsing is sufficient).  It fills up the memory, and LDD is 32bits, so its memory usage is limited.

Interesting... so the lxf file themselfs cant go wrong because they have no "memory"? but the LDD program itself can get slow? then how come that the lxf files continue to open slowly after reinstal LDD on different harddrives, even on other pc and the same lxf files are still loading slow.  Could the LDD memory be flushed in some way?

19 minutes ago, sed6 said:

I think I understand. So with each module being a seperate file have you imported each module into a single large file and saved it? Is that what's running slow? In my experience a large file created by importing many smaller files can run slow. That was a large 5-6k piece file created by a half dozen or so smaller files. I still think creating a new file and pasting in templates as opposed to importing files could be the solution. 

Exacly right, i have also tested by importing only a few of them together and it start gettin really slow... even after a couple of imported file it slows down, Theres a total of about 7-8 different files. But i dont understand what this "templates" is, and nothing happens when pressing ctrl alt g.

[sed6]

A template is like a group but a template is available for use in other models whereas a group is confined to a single model. To create a template highlight (or otherwise select) all the pieces in you want to be in the template. Then hit ctrl-alt-g, the highlighted bricks are now a template. You can verify this by clicking on the templates tab and you'll see it there. Just click on that template to paste it into the new file. This is a useful feature if you want to a) combine several files into a single one like I suggest you do or b) you create a small model that you want to use over and over in different files. Groups are similar, highlight or select all the pieces you want to be in the group and hit ctrl-g, those pieces are now part of a group.  The benefit of groups is it allows you to easily combine or separate groups of pieces so you can modify them or access parts under them.  Once you start using groups and templates LDD gets much easier. I didn't understand why you would create a model and split it between 7-8 different files, that doesn't make sense to me at all. I'm guessing now it's because you're not familiar with templates and groups. Start using the hide button also, that really makes things easier as well.  Once you're comfortable with templates, groups and hide you can create utterly massive builds in a single file and edit and manipulate them with ease. 

Edit to add: click on my sig link and download one of my locomotives, in each you'll see that I've made great use of groups to simplify the assembly, disassembly and modification of the locomotive. Come to think of it, most of the .lxf MOC's I download and look at contain no groups. Perhaps others are not aware of their usefulness. Every time I see a model I think to myself how hard that must have been to create and how much faster and easier it could have been done it only some groups were used...

More edit: if you want to share you .lxf with me I'll be happy to look to see if i can help or to see how it runs on my system for comparison.

Edited June 10, 2018 by sed6

[SylvainLS]

19 minutes ago, GoldVillage said:

Interesting... so the lxf file themselfs cant go wrong because they have no "memory"? but the LDD program itself can get slow? then how come that the lxf files continue to open slowly after reinstal LDD on different harddrives, even on other pc and the same lxf files are still loading slow.  Could the LDD memory be flushed in some way?

They can go wrong because of file system corruption or bugs but the structure is simple so bugs are limited.  The file is read, the objects (parts, connections…) are created in memory, the file is forgotten, you modify the model, you save it, the info is written from memory to the file.  The only thing that stays from your construction process is the order of the parts: a model is “just” a list of parts, each new part is added at the end of the list, so the list is chronological by construction.

And, when read, all the info is checked (e.g. for collision) or (re)created.  For instance, connections and articulation points aren’t mandatory, so they are simply created if they are not present in the file.  I’m sure they are at least verified. That takes time.

I don’t know of any way to flush LDD’s cache, even in Developer mode.  Anyway, that wouldn’t serve when loading a file just after having launched LDD: every thing that is put in memory is needed for the model.

 

[GoldVillage]

1 hour ago, sed6 said:

A template is like a group but a template is available for use in other models whereas a group is confined to a single model. To create a template highlight (or otherwise select) all the pieces in you want to be in the template. Then hit ctrl-alt-g, the highlighted bricks are now a template. You can verify this by clicking on the templates tab and you'll see it there. Just click on that template to paste it into the new file. This is a useful feature if you want to a) combine several files into a single one like I suggest you do or b) you create a small model that you want to use over and over in different files. Groups are similar, highlight or select all the pieces you want to be in the group and hit ctrl-g, those pieces are now part of a group.  The benefit of groups is it allows you to easily combine or separate groups of pieces so you can modify them or access parts under them.  Once you start using groups and templates LDD gets much easier. I didn't understand why you would create a model and split it between 7-8 different files, that doesn't make sense to me at all. I'm guessing now it's because you're not familiar with templates and groups. Start using the hide button also, that really makes things easier as well.  Once you're comfortable with templates, groups and hide you can create utterly massive builds in a single file and edit and manipulate them with ease. 

Edit to add: click on my sig link and download one of my locomotives, in each you'll see that I've made great use of groups to simplify the assembly, disassembly and modification of the locomotive. Come to think of it, most of the .lxf MOC's I download and look at contain no groups. Perhaps others are not aware of their usefulness. Every time I see a model I think to myself how hard that must have been to create and how much faster and easier it could have been done it only some groups were used...

More edit: if you want to share you .lxf with me I'll be happy to look to see if i can help or to see how it runs on my system for comparison.

WOW... how smart was that! :P TY alot! so far so good, they loading fast now. Even several templates put together loading fast! such a simple solution on a, what i believed, hopeless problem. 

[sed6]

Excellent! I'm glad that worked out for you. Happy building!