ffmpeg streaming lag cut pause, when I change crf qmin refs, etc, the lag remains

Question

The question is about tuning a FFMPEG command, not about the context or the use, my setup works, it's only the lag part I'm trying to get smoother....

here the ffmpeg command

ffmpeg -y -f alsa -i pulse -f x11grab -draw_mouse 0 
-framerate $FRAMERATE -video_size $RESOLUTION -i :$DISPLAY_NUM  
-c:v libx264 
-movflags +dash 
-preset ultrafast 
-crf 27 -refs 4 -qmin 4 
-pix_fmt yuv420p 
-c:a aac -ac 2 
-profile:v baseline 
-hls_time 6 -hls_list_size 0 -g 30 
-start_number 0 -streaming 1 -hls_playlist 1 -lhls 1 
-f hls -filter:v fps=$FRAMERATE x.m3u8

I tried changing values in preset, crf, refs, qmin, qmax, profile:v, hls_time......

no matter what I change doesn't fix the "lag" or feeling that it pause,

sample here : https://www.tubfeed.com/_/tubfeed/---/multishare/multimedia/16607032261648

is there any ffmpeg option or attribute that I missed to try ??

Answer 1

After digging a bit I found more flags for low_delay...

I did this and the lag disappeared

ffmpeg -y 
-f alsa -thread_queue_size 4096 
-i pulse -f x11grab -thread_queue_size 4096 
-draw_mouse 0 -framerate $FRAMERATE 
-video_size $RESOLUTION 
-i :$DISPLAY_NUM 
-c:v libx264 
-movflags +dash 
-fflags nobuffer 
-flags low_delay 
-threads 2 
-preset ultrafast 
-tune zerolatency 
-crf 27 -refs 4 -qmin 4 
-pix_fmt yuv420p 
-c:a aac -ac 2 
-profile:v baseline 
-hls_time 6 -hls_list_size 0 -start_number 0 
-streaming 1 -hls_playlist 1 -lhls 1 
-f hls -filter:v fps=$FRAMERATE "/recordings/$VIDEO_ID/$VIDEO_NAME.m3u8"