P: Random white images when exporting or publishing

Geoff it very well could be as I do have a 8 core and a good deal of people complaining about ti have the same, but I do have 2 staff photographers with the same problem that have quads and another with a Imac which I think is a quad if im not mistaken as well

Reproduced in Lightroom 5.7 with no issue. Is there a possibility this is an issue with the graphics processor acceleration? Maybe specifically with AMD processors since it sounds like this is happening with 8 core processors?

Ive been dealing with it for close to a month and 2 of my staff photographers are now dealing with it as well.

im with some that about 15% of my files come out blank/white, and its complete randoms. Ive reexported the same set and it will be different photos that turn out blank than the previous export etc.

I've packed up all the files needed to reproduce the bug, including 50 test photos, the export and watermark presets, and step-by-step instructions:

https://dl.dropboxusercontent.com/u/2...

I've noticed in my environment that the bug doesn't seem to happen when the originals are raw files -- it only happens with smaller JPEGs (the originals are about 3 MB, the exported versions about 860 KB).

Race conditions are notoriously difficult to track down. By definition, race conditions are timing dependent, and it is often the case that they can't be reliably reproduced on different machines. But enough different people experience the bug often enough that even if Adobe can't reproduce it on one of their own machines, they should ask to use one or more customers' machines to reproduce and debug. Using the configuration above, the bug happens every time I export the 50 test files.

The folder also includes a Process Monitor trace of the system calls made by LR when doing a buggy export. LR 6.0.1 uses three passes to export a file: The first pass writes it, the second pass rereads it into memory, the third pass writes it again with slightly changed metadata. For a properly exported file, the first pass writes about 858 KB, but for the buggy exported file, it writes only about 145 KB (and thus it appears blank). It's likely an internal buffer containing the exported file is not being properly locked and is getting reused prematurely by another exported file before LR is finished writing it out to disk.

The trace shows that LR was the only process accessing the originals and the exported files. Windows File Explorer and Bridge were not open on the destination folder. I even turned off Windows Indexing, because it would try to read the JPEGs as soon as they were written.

A workaround to this bug is to run Lightroom on 1 CPU. Download this Windows batch file:

https://dl.dropboxusercontent.com/u/2...

and put it on your desktop. When you're ready to do your export, exit LR and restart it by double-clicking on the .bat file. Then do the export. The export will go much slower, but the chances of encountering the bug will be greatly reduced.

I did some test exports, each with 1000 JPEGs, with varying numbers of CPUs, and here are the number of blank JPEGs produced:

1 CPU: 0
2 CPUs: 6
4 CPUs: 26
8 CPUs: 29

(This was on a 4-core / 8 logical processor machine.) Give that this bug is almost certainly a concurrent-programming bug, it's still possible that you'll encounter the bug when running with just 1 CPU, but in practice, most such bugs happen very infrequently on 1 CPU.

A small clarification: The i7-3700K has 4 cores which present 8 logical processors to the operating system via hyper-threading. Logical processors are also called virtual processors by many. Confusingly, Intel refers to these logical/virtual processors as "threads", which has a different meaning in the software world.

I am getting this same exact issue with my PC Running LR CC, but my yield of error is around 15%. I would like large chunks of white images when exporting. It's pretty bad. Interesting enough, I also have LR CC on my iMac and I DO NOT have this issue. May not apply to many of you, but this may only be an issue with the PC version, just a thing to keep in mind and to note. I rather not use my old iMac for LR.

I just recently built my PC and I rather use that for LR. Also I am in the same postition with Andrej Stern, I have 8 Cores (i7-3770K), LR CC runs on SSD (Windows 7) and exports to an internal HDD. I'm exporting from simple CR2 to JPEG with a PNG watermark

Hi Rikk

Seems really strange that you cannot duplicate the problem with so many of us experiancing it
I have nothing running on my PC when this occurs
sometimes I watermark twice it random fires white blanks only the WM then rerun with a differnt WM over the top and it will fire random again

I can help as much as you want but dont get too techie lol

I have 8 cores (4 physical, 4 hyperthreaded) and lightroom runs on a SSD. I get about 15% blank images in larger batches.