jumps in the CPU useage with x264

[bond]

i noticed that i get lots of jumps in the cpu useage from 100% to 0% and back when encoding with x264 as shown in the attached picture

any idea why this happens?

[yokem55]

Rough guess might be that the encoder is stalling while waiting on mpeg2 data to be read into memory from the hard drive, but the mpeg2 data rate shouldn't be anywhere near high enough to cause that kind of problem unless you have some dma config problems or you have a REALLY slow drive. Another possibility is that another disk intensive task in the backgrond is interupting the read...

[Sergey A. Sablin]

You can select Show Kernel Times from View menu to see how much system is busy itself. You will see red line indicating kernel usage - it can be HDD usage, thread synchronisation, color space convertion via video card drivers (not HW convertion) etc

[bond]

btw i also get parts where these jumps dont happen (as shown below), this seems to be independant of whether i do other things, like surfing around or checking mails
edit: it seems as if at the begin of a new pass there are no jumps taking place and only later on they start (eg after ~1000 frames)

does anyone else get these jumps?

my avs script is

LoadPlugin("C:\...\DGDecode.dll")
mpeg2source("d:\...\source.d2v")
trim(14,7129)
crop(2,82,716,416)
LanczosResize(720,288)i get it with various different x264 commandlines (eg
x264 --pass 2 --bitrate 770 --bframe 3 --b-pyramid --ref 5 --filter 6:6 --8x8dct --analyse all --weightb --progress -o output.mp4 input.avsYou can select Show Kernel Times from View menu to see how much system is busy itself. You will see red line indicating kernel usage - it can be HDD usage, thread synchronisation, color space convertion via video card drivers (not HW convertion) etcthx for the tip i enabled it and saw that the kernel time and the cpu jumps are not taking place at the same time (pic attached below), but still i also get these "to 100%" jumps there, what does this mean? that the jumps are caused by x264 (as not caused by something else, like hd useage aso)?

[yokem55]

Hmm...how is the fragmentation on that hard drive? If the vob file (if that's what your're encoding from) is heavily fragmented this may explain what is going on. The beginning of the file may not be mostly contiguous, but after that the file is getting spread out all over the disk....Just a guess..

[bond]

hm i reformated the hd two weeks ago. how can i check the status of the vob (its actually a small vob only containing the scene i use for testing)

[yokem55]

Okay...if the vob is small enough and there is pleny of free disk space, I doubt then that is the problem. If you want to check the state of the file, run the regular defraging program and have it do an analysis of the partition in question. Then view the report. That report will list out files that are fragmented. If your vob is in that list with several hundred fragments, then that might be the issue.

[bond]

will try, thanks!

[bond]

the vob isnt listed as being fragmented ^^