Question / Help Bad lag only on streams.. please help

[DryReef]

Obs log: https://obsproject.com/logs/6qIgRdMRjLEpYo_3

Been getting this frustrating issue the last 5 days... Didnt have issues with these settings for the past few months and all of a sudden now its dropping frames on the stream... frame rate looks completely fine on the gaming pc and on obs preview on streaming pc.
In case you're curious here's my hardware:
encoding/streaming pc:
i7 8700
16 gigs ram
gtx 1050ti

Gaming PC
i5 7600k
16 gigs ram
gtx 1080
Both computers connected with cat 7 cables to router/modem. Internet is with Spectrum, speed is 400 mb/s download, 20 mb/s upload
Obs settings on streaming pc
2500 bitrate (tried going as low as 1000 and buffering still happened!! wtf)
cpu preset: placebo or very slow
As i mentioned before, i didnt have any issues with any of this for the past couple months until a few days ago
You can see the buffering issues i been having on my twitch here http://www.twitch.tv/dryreef/v/313971446?sr=a&t=522s

 

[koala]

23:56:30.632: Video stopped, number of skipped frames due to encoding lag: 18537/43711 (42.4%)

Your encoder is overloaded. Your CPU is not powerful enough to encode with this settings. Switch from veryslow preset to veryfast and try again. That preset should work without skipped frames due to encoding lag. To test if your CPU is able to handle other presets, try them one by one but only step by step. Any preset beyond "fast" will only add computing stress but not visibly change your output.

 

[DryReef]

Thank you for this. I just find this out before reading your reply.. i thought having a second PC dedicated to encoding would be able to handle slow presets. It's been working on very slow for the past 2 months. I messed around trying slobs and ndi, testing on YouTube etc. And strangely enough the frames stopped dropping when I got to medium CPU preset. I'm still really surprised how this is somehow affecting the frame rate on the stream. I thought CPU preset only affected the CPU! Not the internet or output onto the stream! As I mentioned before I wouldn't see frame drops in the game or on the obs preview on the 2nd encoding pc.. just the stream! So weird!

But I'll be happy to stream regularly again with ndi and the two computers at better quality again tomorrow!

 

[koala]

Of course the CPU preset only affects the CPU, but the CPU affects the stream. You can only output what you are able to encode. If you activate a slower preset, the CPU needs more time to encode a frame. For 60 fps video, a frame is produced every 16.6 ms (milli seconds; a thousandth of a second). If encoding a frame takes more than this 16.6 ms, you have to throw away the next frame. This is a lag. If this thrown away frame is a key frame by chance, all following frames up to the next key frame are destroyed as well. This makes a video coppy and look like a slideshow.
Its like you're filling a tub of water faster than some other person can drain it: it will overflow and the water is spilled and wasted.

 

[DryReef]

I was going at 720p 30 fps tho for the past month and didn't have issues before.. why you think it started acting up?

 

[koala]

I will not start to speculate. But things don't change on their own.