Mike Chaney's Tech Corner

As title only 8 to 10% of processors capacity is being used while printing.  I've checked the processor affinity in task manager and it shows all cores are selected (windows 10). I've tried all variations of multi processors setting have been tried in qimage, looking for ideas as to how to resolve issue.
Sorry for abrupt post but I'm sat in a field trying to type this post in between photographing horses going past me every 2 mins :-)
Thanks

Chris,
If I take your question literally, that Q image is showing less than 10% CPU usage while printing, that would be normal.
Qimage has nothing to do at all after the processing is done and the file is sent to the spooler. The CPU drops off to almost nothing especially while the printer is printing.
The computer is running the show, and feeds data to the printer as fast as the printer can use it.

Fred

Whoop's, I meant when I hit the print button and it starts to process the queue  :o

Hi Chris,
I really don't know how I could tell how many cores/threads were being used at any given moment except for timing.
First of all, see my attached screen snap and see if you have your multi cores turned on in Qimage.
If not, turn them on...
If they are alrady turned on, time how long it takes to complete the processing.
Then set it to 1 core, and time it again.
See what you get.

Fred

Let's start with the basics.  Look at the splash screen when first starting QU.  How many cores does it report on the splash screen?  It should report 8 for an i7 5720.

Edit: that splash screen is a good indicator because the number of cores is the number of threads it will spawn for printing (provided you have multi-threaded printing set to auto or 8 ).

Mike

Qimage recognises 12 cores on start up screen.
I've tried all the setting on the print processing screen and done test and they all take the same time (task manager indicates activity on one core only)
I a mentioned previously task manager also shows that all 12 cores should be used for qimage (affinity settings)

Well that's the strange part.  If it says 12 cores on the splash screen and you have multi-threaded printing set to "Auto", it's going to spawn 8 threads.  At that point, we're down to the operating system not allowing but one core.  Since 8 threads are running, it's up to the OS to assign them each a core and if it's only using a single core, something is preventing that.  Normally that's controlled by the affinity, but I've seen cases where something in the shortcut may cause that.  Are you starting it from a desktop shortcut?  Maybe try deleting the shortcut and then reinstalling QU so it creates a new one.

Mike

Yes I'm starting it from the desktop shortcut, I'll delete/reinstall it as soon as I get back to the trailer.  I'm trying to come up with things to try when I get back, my wife is pulling her hair out as she is having to do all the printing while I lounge around in a field taking the photos :-)

Thanks for the suggestions,. Nothing has worked though.I've uninstalled it and reloaded with new shortcut, I've also tried starting from the .exe file.with no difference in processor usage.  Any other ideas??  ??? ???

Knowing that QU is running 8 threads, we're down to the system/OS not assigning them properly.  The only other thing I can think of is going to MSCONFIG and the boot options, advanced, and making sure "Number of Processors" is NOT checked.  Might want to check multi-core options in your BIOS as well.  Also, try running another CPU intensive app like a video editor to produce a video, or maybe a video converter.  Since all multi-threaded apps work basically the same way (by just spawning multiple threads), if other apps are using multiple cores and QU is not, then something is is making app specific settings to set QU to one core specifically.  At that point, you need to look at app/shortcut settings or consider the possibility that something like an antivirus program is interfering.  Since you've checked affinity and found all CPU's checked, I'm leaning toward the probability that all apps on your system are limited to a single core.

Mike

I've.just tried the msconfig setting before you replied,.it didn't make a difference (box was unticked already, also tried it with 12 cores enabled) :'(
Other apps are using all cores fully.  I'm going to try the BIOS next, thanks for the ideas

You should probably run another multi-threading test in QU too.  Go into a folder with a bunch of images (say 25 or more, preferably raw photos), and use "View", 'Rebuild Thumbs".  See if more than one core is being used while it is building thumbs and the problem is confined just to the printing part.

Mike

Just tried changing settings in BIOS, no difference to print CPU usage.  Tried creating thumbnails and qimage uses up to 75% CPU, so it can use more CPUs but isn't when processing the print queue??

OK update, tried printing to a different printer (12x8 dye sub and CPU usage is higher (up to 37% usage with multiple cores, though one core appears to be doing most of the work) but when I set interpolation to OFF it reverts to only using 1 CPU core (this is the setting that I've been using on the other printer (6*8 dye sub) as it was always the fastest in qimage studio).....
I've now tried this in the original printer and the same thing happens (CPU peaks momentarily at 24%).
Core 6 seems to be doing the majority of the work and interestingly when editing an image with qimage this is the only core that appears to be used (I've tested using the rotate function as this always slowed my old computer down). Is qimage meant to use multiple cores when editing images??

Edit..when printing to file qimage is again using about 9% CPU (1 core is showing usage)

Thanks again for the help

Wow, I didn't even think to ask you if you had turned off interpolation.  It's the interpolation that runs on multiple cores so if you turn it off, there's nothing to multi-thread: it just sends chunks of the image to the driver so no need to multi-thread that.  So that explains it.  In the editor, only the USM/DFS sharpening is multi-threaded.  QU only multithreads the time intensive operations like thumb building, raw cache building, and printing.  USM/DFS sharpening will use up to 4 cores because that operation is computationally expensive and is used in multiple areas of QU.

Mike

Okay, mystery solved !!!  Unfortunately I've just spent lots of money on a new computer that's no faster than the old one  :o haha!
Odly the old qimage studio processed the queue much faster with interpolation turn off on my old quad core machine?
Would there be any chance of multi threading the rotation tool in future as it can slow editing down quite a bit, especially if other alterations are made after correcting rotation.......at least a bit more of this CPU could get a workout  ;D ;-)

Thanks for all the advice

Ultimate is actually faster, so the only reasons for Studio processing faster would be things like page size, driver settings (driver resolution), picture size, etc.  I'd leave interpolation turned on and let it do its job.  With 8 cores running, it'll be almost as fast as interpolation "off".  Rotation is not really conducive to multithreading due to the dynamic pixel location calculations.  What sort of rotation are you doing?  I've never really noticed it taking any significant time.  Are you running very high res photos or something?

Mike

Mike you are right about the speed (well almost  ;) )
I just ran some tests and using the same settings on my old computer (quad core) the time to completion was approx 1\3 faster with interpolation turned off.
On my new computer (6 cores plus hyperthreading) all times ARE faster but turning interpolation OFF actually slows the processing of the queue! Very odd.

Anyway at least they are now going faster than at the beginning of the weekend

Thanks for all you help
Regards
Chris

There are so many variables here that it's difficult to know what you are comparing on your interpolation-off test.  We've tested it here and find QU significantly faster.  As an example, five 8x10's, same printer and driver, same settings, profile, etc. interpolation off, on an i7 4770 machine (4 physical and 4 logical cores):

Studio: 15 sec
QU: 6 sec

That said, there have been many bug fixes in QU WRT how data is sent to the driver, many updates to the color management engine, and so on.  Some of those relate to how to reliably send data to newer drivers and be compliant with Windows 10.  Some of the changes relate to getting the proper acknowledgement from the driver before sending the next chunk of data, formatting of the data, etc.  So I suppose it's possible that, depending on how the driver responds and your particular setup, the timings may be different.  But I still think you likely aren't comparing apples to apples and something in your Studio setup is different than that of QU.

With all that said, I still don't see the logic in buying a machine with 6 physical and 6 logical cores, only to turn interpolation off.  Interpolation is where QU shines.  Any interpolation would be better than none.  If you really want to see it fly, choose a less complex interpolation like "Vector" and watch it fly!

Mike

Thanks mike,
As I mentioned in my last post after timing both qu and studio I found that qu was a bit faster than studio on my old machine,.for example I timed 5 high res JPEG printed as 6x8inch prints with interpolation OFF studio took 34 secs and ultimate took 33 secs.  Turning interpolation on gave 39 secs for ultimate and 44 for studio.
On my new machine using ultimate the same images with interpolation OFF took 23 secs but with interpolation ON only took 17secs, this is what I couldn't understand (this is because I don't know what is actually happening under the hood).
Interestingly the times you have quoted seem substantially faster than I'm getting.
I did time the 5 prints with both fusion and vector and for me both were almost identical speed.  But I'm am at least happy that my system is running faster than my old one though not by as much as I'd hoped.
The reason for the system is that it also creates webpages of all the days images for display in my trailer and at this it IS very fast :-)
Looking at it now I probably would have been better getting a quad core that ran at a higher clock rate, this one is over clocked to 4ghz and I don't need the 32gb ram as nothing I have seems to use very much of it, oh well live and learn :-)  Also I didn't want to buy a new machine but the old one started to be unreliable, so it was time for a change :-)

Yeah, I'd just leave interpolation on and not worry about it.  With it off, there's only one thread running which does nothing but crop out tiles of the main image and send them to the driver.  With interpolation on, there are 8 threads running so I suppose, depending on a lot of factors like amount of interpolation, sharpening, etc., ON could actually be faster than OFF because it actually might be able to interpolate and crop faster than one thread just cropping.  It's gonna be very fast either way so using the interpolation is a win-win.

Mike