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Transcode - Server said to be not powerful enough but CPU not maxed out

t2pierret2pierre Posts: 59Members ✭✭
edited July 2017 in macOS/OS X (Mac)


I have a mac mini running as a PMS (with local PMS database)
All media files are stored on a NAS on the same network than the mac mini.
From remote, when I want to play a H264/20Mbps movie file, I request for a max 4Mbps bandwidth.
Transcoding session starts as it should.
But soon, I got a message saying that the PMS is not powerful enough to sustain a réal time transcoding session.
But when I look at the mac mini; the CPU is only around 20-30%.
Strange thing: the network accesses at the mac min are about 100Mbps in and 100Mbps out (at the max speed on my LAN).
Strange things: 100Mbps is above the H264/20Mbps bandwidth, which is OK, the PMS is fetching the file to transcode it -> but then what are these 100Mbps going out? Is there a link with the PMS poor performance for transcoding?


  • t2pierret2pierre Posts: 59Members ✭✭
    edited July 2017

    Ok, I did the same exact test with the same file stored in the mac mini.
    Transcoding is working fine. CPU is maxed out!
    It seems that the transcoding process is not only depending from the NAS to retrieve the file to transcode but also to convert it. This is not supposed to, right?
    A bug?

  • t2pierret2pierre Posts: 59Members ✭✭

    to make it clear: when I playback the movie with PHT local on the mac mini, it is fine. playback does not respire transcoding in this case. So the NAS performance and LAN bandwidth are good to playback the movie.
    The issue is definitely with trancoding

  • luiz3luiz3 Posts: 2Members

    I am going to say that my Mac Mini Plex server (Late 2012) 2.5 ghz with 4 gig of Memory is having the same issue.

    Observation is that this commenced with the most recent version of Plex Server (August 2017)

    • I shutdown everything and PLEX is the only thing serving and I only have 1 video open
    • Plex is NOT serving anything else - No Photo Nothing etc.
    • when I run .mkv files I am receiving that error.
    • smaller files in .avi format seem to be fine
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