multiple access to vrmeshes (locked files), production in danger

[CGEV]

Hi,

We are trying to render scenes that link many vrmeshes files through our renderfam (windows 7 |maya 2013 render.exe|royal render |vray 2.31).

We've noticed that once a render thread has started loading vrmeshes, no other process ( maya in GUI or any other instance of render) can access the vrmeshes files.

We've immediately thought of file locks that would be put in an inappropriate way , and tried several things.

We know that the render process locks files in write (ie can't overwrite nor delete) , but windows can still read and copy the files.

We've tried removing write rights to everyone to make sure no write lock should be put, but it results in : cannot load vrmesh file.

There seem to be a limitation or problem in the way maya render + vray for maya lock the vrmesh files.

Can you please help, we are in the big rush of a production, and can't render on more that one machine at a time, nor work using with the same vrmeshes while render runs.


Rgds

[CGEV]

EDIT: I forgot to mention that each vrmesh contains all the frames of the shot, for one character. (not 1 vrmesh per frame per character)
+
we've just tested exporting in vrscene and rendering using standalone, same issue.

[vlado]

Thanks for the pointer; will look into it. Do you have access to the V-Ray nightly builds?

Best regards,
Vlado

[vlado]

Hmm, actually now that you mention it, this has never been an issue and many many customers over the years have been using .vrmesh files on shared network locations without any issues.

Can you show me the exact error messages printed out by V-Ray?

Best regards,
Vlado

[CGEV]

Yes we have access to nightlies if required,so far i didn't seem to find any mention of such issue the changelog .

[vlado]

Yes we have access to nightlies if required,so far i didn't seem to find any mention of such issue the changelog .

No, like I said this has never been an issue and we don't really lock the .vrmesh files. Can you show me the exact output from V-Ray?

Best regards,
Vlado

[CGEV]

There is no error message by default, just that we notice we are locked and can't use the vmreshes anymore:
If we submit a render, even with just 1 render node, and we try to import the vrmeshes in maya gui, it remains freezed until job is finished or killed.
I we submit job on multiple nodes and chek the logs with attention, we see that the first node that starts rendering links to the vrmeshes very quickly, then all the other render nodes seem to be waiting, and the logs show us that linking the vrmeshes takes huge additionnal time (like 20 minutes or so). ( in the storage logs and graphs, there seem to be absolutely no issue of load or bandwidth).


We didn't mention that each vrmesh was about 100/200MB and there are 500 of them in the scene. (each vrmesh contains all the frames for one character).
We were thinking of rendering vrmeshes per frame per character ( it will end up to approx 250000 small files instead of 500 big), what are your thoughts about that ?

thanks a lot

[bigbossfr]

Did you try to render 1 vrmesh in two different computers witthout royalRender ? (perhaps it is RR...)

[vlado]

We were thinking of rendering vrmeshes per frame per character ( it will end up to approx 250000 small files instead of 500 big), what are your thoughts about that?

For your particular case this might work better. Still, we don't really lock the files, but I will run a few tests with the latest stable 2.3 release just to make sure.

Best regards,
Vlado

[CGEV]

Did you try to render 1 vrmesh in two different computers witthout royalRender ? (perhaps it is RR...)

Yes, first thing we tried, rendering the same command (render.exe -vray ....) from a cmd commandline on a workstation, same issue, one rendering prevents access for any user.

[CGEV]

For your particular case this might work better. Still, we don't really lock the files, but I will run a few tests with the latest stable 2.3 release just to make sure.

Best regards,
Vlado

tomorrow we'll rewrite our batch proxy exports to render frame by frame (though is is less efficient in generation), and test.
TO be more precise about the locking, here is what we see:

1/when a render is running on one node or more, windows explorer can read and copy to another location the vrmeshes.
windows explorer cannot delete or move the file stating that is in use ( which is true )
maya through gui cannot import the vrmeshes (freeze)
any other render seems to struggle to get acces to vrmeshes and waits.
2/ when render is finished or disabled, windows explorer can read, copy , moce delete the vrmeshes
maya can import vrmeshes

If we change the file rights so they are read-only (which possibly prevent to put a write lock), vray fails to load the vrmeshes ( like it requires a read-write access to the files).

I've tried to disable handling of locks on my file server ( which is hihgly unrecommended to prevent file corruption) and it changes nothing.

it behaves like both vray rendering and proxy/import/loading in gui requires more locking than expected ( we would expect a file read lock or something like that)

Rgds

[vlado]

Hm, a quick test here with a read-only .vrmesh file works as expected (V-Ray can render it just fine). But this is with a newer V-Ray version; will try 2.3 tomorrow.

Can you show me the error message that you get in that case?

Best regards,
Vlado

[CGEV]

Hm, a quick test here with a read-only .vrmesh file works as expected (V-Ray can render it just fine). But this is with a newer V-Ray version; will try 2.3 tomorrow.

Can you show me the error message that you get in that case?

Best regards,
Vlado

sorry I dd'nt see you wanted this particular error:

when the files are forced read only:

Warning: Could not load mesh file:"###path to my vrmesh file####"

Did you get the chance to check on 2.31 version on your side ?

we have generated new vrmeshes by frame, just need some modifications of our import scripts and we'll be able to test with those files.

Rgds

[bigbossfr]

The best to know if it is a VRay problem or not is, on 1 computer :
- create a .vrmesh into c:\ (it is important, not on shared folders or network folders)
- open 2 Maya, render at the same time (on the same computer obviously)

[vlado]

Did you get the chance to check on 2.31 version on your side ?

Yes; unfortunately (or fortunately, I don't know) everything works as expected here; even when the file is read-only on a shared network path, we are able to successfully open and render it in several instances of Maya on different machines.

Best regards,
Vlado