[FFmpeg-user] Throughput /Performance isssue

[eric cocuzza]

Hi Guys,
I am using ffmpeg for my trans coding and see some beard behavior, If with the previous versions of ffmpeg and libx264 i do transcoding it takes x FPS to complete it. when with the latest ffmpeg which has lot of assembler modifications should improve my trans coding time together with FPS. I did see my FPS goes about 30% better compared to the previous trancode but Throughput which is (MBPS per CPU percentage) goes higher by 45%. which is surprizing me?
Could someone suggest me the reason behind it? Looking forward for the response. He is my ffmpeg command line with new and old ffmpeg+libx264
#Commandline#ffmpeg -y -i 3G1PFLuTrgM.flv -vcodec libx264 -coder 0 -flags +loop -cmp +chroma -me_method epzs -subq 2 -me_range 16 -bf 0 -refs 2 -trellis 0 -x264opts no-mixed-refs:no-8x8dct:no-mbtree:weightp=0:b-adapt=0:no-deblock=0:partitions=i8x8,i4x4:no-weightb:ipratio=1.41 -threads 1 -wpredp 0 -rc_lookahead 0   -g 250 -keyint_min 25  -sc_threshold 40  -i_qfactor 0.71  -b_strategy 1  -qcomp 0.6 -qmin 10 -qmax 51 -qdiff 4 -crf 28 /tmp/test1.flv&
Results with latest ffmpeg+libx264 transcode (10 concurrent Trancode per session)frame= 5085 fps= 38 q=26.0 Lsize=16394kB time=00:03:32.08 bitrate= 633.2kbits/s    video:16294kB audio:0kB global headers:0kB muxing overhead 0.612624%[libx264 @ 0x24ceb40] frame I:147   Avg QP:24.76  size:  8813[libx264 @ 0x24ceb40] frame P:4938  Avg QP:30.46  size:  3116[libx264 @ 0x24ceb40] mb I  I16..4: 58.7%  0.0% 41.3%[libx264 @ 0x24ceb40] mb P  I16..4: 12.9%  0.0%  3.3%  P16..4: 34.7%  0.0%  0.0%  0.0%  0.0%    skip:49.2%[libx264 @ 0x24ceb40] coded y,uvDC,uvAC intra: 24.6% 2.2% 0.5% inter: 14.4% 0.5% 0.0%[libx264 @ 0x24ceb40] i16 v,h,dc,p: 39% 38% 15%  9%[libx264 @ 0x24ceb40] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 28% 20% 27%  4%  4%  5%  4%  5%  3%[libx264 @ 0x24ceb40] i8c dc,h,v,p: 96%  2%  2%  0%[libx264 @ 0x24ceb40] kb/s:629.35
Results with Old ffmpeg+libx264 trancode (10 concurrent Trancode per session)frame= 5085 fps= 32 q=26.0 Lsize=   16140kB time=00:03:32.08 bitrate= 623.4kbits/s    video:16040kB audio:0kB global headers:0kB muxing overhead 0.622325%[libx264 @ 0x3297b40] frame I:147   Avg QP:24.76  size:  8813[libx264 @ 0x3297b40] frame P:4938  Avg QP:30.59  size:  3064[libx264 @ 0x3297b40] mb I  I16..4: 58.7%  0.0% 41.3%[libx264 @ 0x3297b40] mb P  I16..4: 12.3%  0.0%  2.6%  P16..4: 35.9%  0.0%  0.0%  0.0%  0.0%    skip:49.2%[libx264 @ 0x3297b40] coded y,uvDC,uvAC intra: 22.5% 2.2% 0.4% inter: 14.2% 0.6% 0.0%[libx264 @ 0x3297b40] i16 v,h,dc,p: 39% 39% 15%  7%[libx264 @ 0x3297b40] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 29% 21% 26%  4%  4%  5%  4%  5%  3%[libx264 @ 0x3297b40] i8c dc,h,v,p: 96%  2%  2%  0%[libx264 @ 0x3297b40] ref P L0: 81.2% 18.8%[libx264 @ 0x3297b40] kb/s:619.54
Any quick response highly appriciated.
Eric