Hi @ all,
I just noticed Jason from ByteMyBits said in his latest video that 1GB/stream is enough free space when transcoding.
Has this changed from the old “you need at least the file size + 100 MB of free space”? I am asking because RAM is expensive and I “only” have 16GB (of which 8 GB are a RAMdisk for plex transcoding folder).
Best wishes!
@naddel81 said:
Has this changed from the old “you need at least the file size + 100 MB of free space”?
This has changed since quite a while already.
The next beta version may have a little update to improve behaviour with small transcoder cache drive even further.
Keep in mind though:
if your transcoder cache gets too small, you’ll seriously impede user comfort when they skip back on the timeline in Direct Streamed and transcoded videos.
Because the video packets, that were already transcoded before, might have gotten thrown out of the cache automatically, only a few minutes after they were played the first time.
So the transcoder has to transcode them again, with all delays and/or sluggish behaviour that comes with transcoding (particularly if your server is under load or has not a big CPU).
so how does transcoding work now opposed to “then”? are 8 GB RAMdisk enough?
how much space is needed for a full movie?
@naddel81 said:
so how does transcoding work now opposed to “then”? are 8 GB RAMdisk enough?
how much space is needed for a full movie?
That cannot be said, because it depends on which quality/bitrate you are transcoding to.
And since Plex is a ‘server’ that can be used by several users and/or clients concurrently, you need to take that situation into account as well.
2 concurrent playbacks , 3 concurrent playbacks, 4 … - you get the idea
I assume 8 GB would be perfectly fine for movies in 720p/4mbps and for many movies in 1080p/8mbps.
But as I said above, there is an update in preparation which improves the situation,
if you are willing to sacrifice the ability to quickly jump back in the timeline.
so if I understand you correctly, plex keeps the whole movie (transcoded only) until it is finished?
and it deletes on the go if space is insufficient?
how did this change in the past?
@naddel81 said:
so if I understand you correctly, plex keeps the whole movie (transcoded only) until it is finished?
If it has the storage space, yes.
and it deletes on the go if space is insufficient?
how did this change in the past?
This deletion was either not done or only under certain circumstances.
so 10 GB should be sufficient for all situations where users only pause the stream or skip a few minutes back to check on something they might have missed.
do you know if plexPy can give stats on the size of the transcoding folder?
@naddel81 said:
so 10 GB should be sufficient for all situations where users only pause the stream or skip a few minutes back to check on something they might have missed.
I guess so, unless they become too numerous 
do you know if plexPy can give stats on the size of the transcoding folder?
I don’t think so.
let’s do the math: If I have a transcoder render 5 minutes ahead and the last 5 minutes already shown (8 mbit/s at 1080p) then it would take up 600 MB for that 10 minutes.
at 10GB cache space that would give me at least 15-16 streams at the same time. I do not think I have as many users or even CPU performance to handle it. I would consider even 6 streams (transcoded) at the same time to be unrealistic for my use scenario. internet upload bandwidth is another issue here 
so for my 2-3 streams (max.) I am fine with 10GB transcoder (RAM) cache, right?
@naddel81 said:
so for my 2-3 streams (max.) I am fine with 10GB transcoder (RAM) cache, right?
I’d simply try it out.
And remember to repeat the test when the next beta is released.
can I somehow see how much space is used (max) on that drive without having to check it all the time?
@naddel81 said:
can I somehow see how much space is used (max) on that drive without having to check it all the time?
No.
I guess I found a tool that does exactly what is needed here:
