x265 transcoding bugs when running unattended

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jsmcvoy
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x265 transcoding bugs when running unattended

Post by jsmcvoy » Sun Jan 04, 2015 6:41 am

First, I love your software and am grateful to have it. I'm running the 64-bit version of the latest build; 0.8.33.5680. I generally queue 10-60 jobs - high bitrate 720p & 1080p, mkv files which I transcode to low bitrate mkv files in 720p or 480p using Quantizer QP - and let them run unattended, usually overnight. This has always worked fine with x264, but since using x265 I find that the queue transcode just fine as long as I'm actively using the computer to do other things (runs between .35X & .48X ) but when I leave it unattended the speed drops to something like 0.6X so that I generally don't get even 1 file completed overnight. There is obviously some sort of bug and I'm hoping you can fix it in a new release, hopefully soon. - Thanks :)

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Re: x265 transcoding bugs when running unattended

Post by stanley » Fri Jan 09, 2015 8:50 pm

The reason is x265 is not as good as x264 in utilizing all computation power of multi-core processor. This is not bug.
When things work together, things work.

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Re: x265 transcoding bugs when running unattended

Post by jsmcvoy » Sat Jan 10, 2015 6:41 am

Actually, I'm having the same problem when transcoding in x264 as well. The speed drops to, at most, 1/10th of normal speed soon after I leave the computer unattended with the software running. When I said speed of x265 transcoding drops from ~.35-.48 to ~.6 I actually meant to say ~.06. Now, after switching to earlier versions of MediaCoder twice, since the problem only cropped up after I updated my old version (probably released in February when x265 beta was shown in news feed) I further refined my testing results. When transcoding in x265 at "Normal" priority I get ~.5-.6x speed consistently while I'm actively running anything else on my computer, even simply playing a video file. When I leave it unattended overnight, I find that the speed drops to ~.016 to, at the very fastest (not consistent) when running in "Auto" priority ~.05x. As you can see, to say that my speed drops to, at best, 1/10th of normal is being very generous. And, as I said, the unattended transcoding speed differential when transcoding in x264 is very similar. The program has simply stopped running properly when unattended, for me at least, to as far back as the 0.8.31 build 5645 version, released on 7/28/14, which is as far back as I've gone so far. I suppose I may try loading even older versions, but then I'm afraid I'll be risking more problems by sacrificing improvements you've made to the x265 capabilities recently. Please help. This is very frustrating, as I transcode a great many files, to save space on my pc while preserving good to decent quality, and do most of it while I'm away from my computer; or at least I used to. :( Thanks very much for responding and in spite of my recent complaints, I'm very grateful for all the work you're doing and am very happy to have MediaCoder.

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Re: x265 transcoding bugs when running unattended

Post by jsmcvoy » Sat Jan 10, 2015 6:52 am

p.s.; I'm using the latest Intel 8-core processor (Intel® Core™ i7-5960X Extreme Edition Eight-Core 3.00GHz 20MB Intel Smart Cache LGA2011-V3) on an Assus x99 Deluxe (ASUS X99 Deluxe ATX w/Wi-Fi 802.11 AC 2.4/5 GHz, Dual Intel GbE LAN, 5x Gen3 PCIe x16, 1 PCIe x4,1x M.2, 10x SATA 6Gb/s) motherboard with 32 GB of DDR4 memory (32GB (8GBx4) DDR4/2400MHz Quad Channel Memory [+330] (Corsair Vengeance)) and a decent graphics card (AMD Radeon R9 290 4GB GDDR5 PCIe 3.0 x16 Video Card) and running Windows 8.1 Professional so my system's performance shouldn't be an issue, unless there's a conflict with running MediaCoder on 8.1. I did switch to 8.1 at the same time as upgrading my Mediacoder software to the latest version, which is when this problem began.

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Re: x265 transcoding bugs when running unattended

Post by fredbe9300 » Thu Jan 15, 2015 9:12 pm

as a computer engineer, I found this an fascinating subject, though I know nothing of it, and haven't used x265 myself. Happy user (donated :) ) of the x264 recodes

peculiarly, when googling "x265 vs x264 cpu utilization", some of the top links (albeit 1,5 years old now, and potentially totally obsolete given the recent rise of x265), state the opposite: x265 using multicore better than x264.

e.g. this article and its links: http://tech-beta.slashdot.org/story/13/ ... s-hevch265

the odd and essential thing that OP notices, is that x265 works much faster if he (the user) is doing something interactive on the computer to "keep it awake". that sounds like a bug, but might be in x265.exe; or even in OP's version of Windows.

@ jsmcvoy : have you tried playing with the process priority levels ?


kindly,
Fred

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Re: x265 transcoding bugs when running unattended

Post by fredbe9300 » Thu Jan 15, 2015 9:19 pm

to maintain overview, it might be best to merge this thread and the bug thread, viewtopic.php?f=28&t=13324 or to close one of the two?

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Re: x265 transcoding bugs when running unattended

Post by stanley » Fri Jan 16, 2015 12:46 pm

Have you guys tried enabling parallel options of x265 (click Advanced button)?
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Re: x265 transcoding bugs when running unattended

Post by jsmcvoy » Fri Jan 23, 2015 8:39 am

@ jsmcvoy : have you tried playing with the process priority levels ?
I've tried the different priority levels within the MediaCoder UI, but not directly on the Windows services for MediaCoder, x265 or x264. Unfortunately, I seem to be having the same problem -- program slowing to almost 0.01% when left to transcode while the computer is unattended -- with both x265 & x264, in the more recent Mediacoder versions/builds. I've been out of town, and not doing any transcoding, for some time and am now a bit foggy on the performance of the program using x264, so I'm going to leave a batch running tonight in that format to confirm this fact, if only for myself. I'll get back to you guys with the result. I am still positive that processing in x265 is bugging out -- dropping to almost 0.01% when left unattended -- and have tried reverting to earlier builds - have gone back as far as version 0.8.31 build 5645 released 07/28/14 (64-bit). I have not tested any of this with the 32-bit version.

~peace

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