Render Hang

Started by TheBadger, August 01, 2012, 05:04:08 PM

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TheBadger

Hello,

I have a render that has finished. However, the render screen is stuck between "rendering" and "finished rendering". That is, I have a color wheel that is spinning and has been for some time. The Image is totally finished rendering as far as I can see.

How can I save my image?!!!!?!?! It was a 32hr render.
It has been eaten.

Tangled-Universe

Bummer :(

Did it finish eventually or did you abort it?
Something similar has just been reported elsewhere so I think Matt may be interested in taking a look at your file(s).
Let's see what he says when he reads this.

Cheers

TheBadger

Hey Martin,

It finished. After about an hour long hang. After I reported here I turned off wifi and all other apps and then put the monitor to sleep. After I came back it had finished.

I resently pulled all of my memory and sent it back to "OWC", because some of the sticks went bad (lifetime warranty ;D) So I'm down to my original 8GB for the moment. This does have an affect on my system when TG2 is running

I am absolutely sure this issue, in this case, is because of my population sizes, and file sizes of my plants. Well, I mean that I can't see any other reason.
Most of my own objects have 4k png textures. And I see that this is problematic now.

This mushroom project thing has revealed a lot of issues so I will finally try to zip everything and send it in. Hopefully doing so will help out.

Live and learn, I guess.
It has been eaten.

jo

Hi,

Taking an hour after a 32 hour render in a situation where you're a bit lower on memory than usual probably isn't unexpected. That time when TG2 seems like its "hung" is actually when it's doing a lot of work. Mainly it's preparing the final image from the render buffers, doing stuff like antialiasing. It's also the sort of work that can be shifting a lot of memory around (especially for larger images and higher AA settings) and if you've gone past the amount of physical RAM you have then that can mean it all becomes very much slower than otherwise.

I think what we need to do is improve the feedback to the user during this final part of the rendering process, so you know work is still going on.

Regards,

Jo

TheBadger

Thanks Jo! It just scared the hell out of me. All I could think is its frozen or its going to quit, and the time lost.

But as long as I know its just a matter of time, I can deal with that.
It has been eaten.

Tangled-Universe

#5
Quote from: jo on August 01, 2012, 08:07:52 PM
Hi,

Taking an hour after a 32 hour render in a situation where you're a bit lower on memory than usual probably isn't unexpected. That time when TG2 seems like its "hung" is actually when it's doing a lot of work. Mainly it's preparing the final image from the render buffers, doing stuff like antialiasing. It's also the sort of work that can be shifting a lot of memory around (especially for larger images and higher AA settings) and if you've gone past the amount of physical RAM you have then that can mean it all becomes very much slower than otherwise.

I think what we need to do is improve the feedback to the user during this final part of the rendering process, so you know work is still going on.

Regards,

Jo

Hmmm...so after rendering and AA'ing the buckets it's doing that again?

How about the issue digitalis posted on the alpha forum?
That was 32 minutes of rendering with 20 additional minutes at least. Could be even longer if he hadn't aborted it himself.
It was my scene and it doesn't use much memory (for a change lol), nor has it populations as Michael suggested.

I hope you guys are able to sort it out, because when working with a renderfarm this costs much much money :)

EDIT: just read it may be related to CPU timings? Michael, did you do anything out of the ordinary with your CPU or does it use some fancy native under/over-clocking tech?

Oshyan

I don't think the issue that Digitalis reported is necessarily the same thing. It's rare but I have seen genuinely "hung" renders before. The problem of long post-completion compute times is still unclear to me, i.e. whether it happens in regular circumstances or whether it's essentially confined to people over-stretching their system resources. I definitely want to find out if it's a TG2 issue though as I agree that it seems overly long for a post-render stage, regardless of the complexity of the render. If primary rendering is complete, I would think that all remaining work must solely be on resulting image buffers, which should be equivalent regardless of scene complexity (I think), and would be influenced only by render resolution and AA level. Having seen extremely high resolution (but simple) images go through the "completion" phase fairly quickly, it's hard to believe this should be normal, expected behavior. At the least, as Jo says, it should give more feedback to the user during that process.

- Oshyan

Tangled-Universe

Yes that sounds good Oshyan. Possibly the client can tell exactly at which stage of completion it hangs?
I think I had this once or twice in the past 5 years, but it's suspicious it shows up twice in such relative short time.
Oh well, with a renderfarm you have so much more chance running into this ;D

jo

Hi,

Just thought I'd say I agree with Oshyan that there are some situations which need further investigation.

Regards,

Jo

TheBadger

Quotedid you do anything out of the ordinary with your CPU or does it use some fancy native under/over-clocking tech?

I recently installed some temperature monitoring software, and fan control software with the intension of future over clocking. But haven't done that yet.
The only things I have been doing out of the ordinary (for me) is experimenting with bucket size and threads. Threads because I was down on memory and I could not even use my web browser while rendering. But I got my memory back today, and I am fast again. ;D

QuoteOh well, with a renderfarm you have so much more chance running into this

This concerns me too! I have some plans to use rendering services in the near future and I'm going to be on a very small budget.

This kind of hang has only happened to me once or twice too, guys. But this is the first time it took so long.

Oshyan
Quotewhether it happens in regular circumstances or whether it's essentially confined to people over-stretching their system resources

In this case, I feel like "over-stretching" is the likely culprit. But you will, I hope, be able to say for sure once you guys see the files.

Ill get them to planetside tonight. Please remember about the other posts I made about this project when you have time to look at it... Thanks guys!
It has been eaten.

Wurby

So do we get to see it? :D
Life's hard. Life's harder if you're stupid.

TheBadger

#11
*edit
oops, wrong thread.

@Wurby

See what?
It has been eaten.

Wurby

Life's hard. Life's harder if you're stupid.

TheBadger

ahhhh, ;)

Yes the render finished but a lot of work left to do. I rendered out the RTO on, now I have to do the RTO off version...Then composite. And actually after looking at the image from the OP I decided to make some big changes :'( So that 32hr 3000pix wide render ends up just being a test render

But it will be up in a day or two here: http://www.planetside.co.uk/forums/index.php?topic=14818.0
It has been eaten.

Wurby

Life's hard. Life's harder if you're stupid.