NetData usage

[MikeG.6.5]

OK, some of you might be wondering the use of this program. I can give a real world example of how NetData can be used on our systems to show over-all usage on the CPU. Take a look at the graphic below:



This is playing a 7Mbps video Direct Playing it from the NAS to the Vizio client app from Plex. The spikes you see to the left, even though they take up 30% or so, are when Plex is initially starting the TV show, so it's expected that there would be a bit more activity. The next spike coming through at about 13:22 is when I opened the same TV show in Plex Web App to verify the bitrate. Again, this increase in activity is expected.

The AVERAGE usage is under 4% of CPU. Remember, the NAS (a 7004T) I have has an i3 in it, with a total of 4 cores. So the scale should be to 400% total. That means that Plex Direct Playing this video uses less than 1% of the total CPU available to the NAS.

Having data like this is important, for setting up a server, and gives some real useful data. I will post one of a session that is transcoded to show the difference in scale of use.

[MikeG.6.5]

Ok, I promised an image of a transcode session. This should put everyone's minds at rest, which is better for the NAS and it's operations.

Take a peak at this image now:



Take a good hard look at the scale on the left side, where it goes to 400%. The start of the session shows how much of the CPU is in use, for about 4 minutes or so, the CPU is maxed out. Now, after the CPU catches up to a certain point, and then the CPU drops down a ways. What happens here is that the CPU gets far enough ahead of the playing part of the media and then throttles back a bit. This is a feature that is somewhat unique to the 7004T and it's larger brothers. As the lower end CPU's haven't got enough juice to ever get far enough ahead.

This particular movie is a 17Mbps 1080p movie playing again on my Vizio TV. Transcoding was forced by setting the levels in the Plex App to 4.0 and the media was converted with levels 5.0. As you can see, there are marked differences in how the media uses the CPU from one version of streaming to the other. Most importantly, the transcode pushes the limits of even the i3 chip in the 7004T NAS. (Just think what it's doing to an ARMv7 or Celeron in some of the other models?)

The importance of doing media conversions BEFORE attempting to stream it shows itself here. By not having the media in the right format, and ready to stream before Plex or another media streaming app gets it is going to cause problems.

I could also have shown things like files in use, disk activity, etc. but I thought this was the MOST important thing to show to start with. Let me know if you think more is needed.