minidlna runs at 100% cpu

[MickSulley]

On a fresh install of Ubuntu Server 20.04.1, LTS I have installed minidlna and it seems to be working OK, however it runs at 100% cpu, occasionally drops to 98% or so but mostly 100%
Is there something wrong or is that normal?

Thanks
Mick

[TheFu]

Well, it does need to index the content in order to serve it. That can take hours, but is dependent on the amount and type of content being indexed.
After that finishes, streaming shouldn't take much CPU at all. I don't think miniDLNA supports transcoding like plex or jellyfin or emby do for each client device.

Are you certain it is minidlna eating the CPU and not something else? What does top show?
Could it be a poorly sized swap problem?

And the CPU would matter. If it is a 10th-gen Core i7, then yes, it is definitely a problem, but if it is an Atom from 2011, perhaps this would be normal.

[TheFu]

I would disable minidlna and see if the CPU abuse continues too.

[MickSulley]

This is what I see in top

  PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND                                                                                          
34129 minidlna  35  15  182760   7848   4400 R 100.0   0.0   1687:34 minidlnad

If I stop the minidlna service then that line disappears from top
The processor is an Intel E5-2420 Xeon Six-Core 1.9GHz CPU, so should have plenty of power. Swap usage shows 1%

[SeijiSensei]

How big are the libraries it needs to index? Once the indexing is finished, my instance of minidlnad uses hardly any CPU.

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND                                                
 3945 phl       20   0  266m 7820 1236 S  0.0  0.2   0:06.14 minidlnad

[ajgreeny]

Let's see the content of your /etc/minidlna.conf file; that may immediately give us more of a clue than we have at the moment and the CPU use you mention is certainly not normal.

I run minidlna on my laptop with the following hardware and my system uses perhaps 10%cpu when indexing the media folders but then reduces to such an extent that it is no longer shown in my top 4 processes as shown in conky's output (See screenshot)

Processor (CPU)		Intel® Core™i3 Dual Core Mobile Processor i3-4100M (2.50GHz) 3MB
Memory (RAM)		        4GB KINGSTON SODIMM DDR3 1600MHz (1 x 4GB)
Graphics Card		        INTEL® HD GRAPHICS MEDIA ACCELERATOR 4600
Memory - Hard Disk	        500GB SERIAL ATA II 2.5" HARD DRIVE WITH 8MB CACHE (5,400rpm)

and with minidlna running all the time alongside firefox with 3 tabs open I see the following CPU % usage as shown in the screenshot
My minidlna.conf file is shown below; it will be interesting to see the differences apart from the folders used.
NB: I have removed my name and replaced with xxxxxx

# This is the configuration file for the MiniDLNA daemon, a DLNA/UPnP-AV media
# server.
#
# Unless otherwise noted, the commented out options show their default value.
#
# On Debian, you can also refer to the minidlna.conf(5) man page for
# documentation about this file.
#
# Specify the user name or uid to run as.
#user=minidlna
#
#
# Path to the directory you want scanned for media files.
#
# This option can be specified more than once if you want multiple directories
# scanned.
#
# If you want to restrict a media_dir to a specific content type, you can
# prepend the directory name with a letter representing the type (A, P or V),
# followed by a comma, as so:
#media_dir=A,/path/to/folder
#media_dir=P,/path/to/folder
#media_dir=V,/path/to/folder
#media_dir=B,/path/to/folder #to browse all file types
#
media_dir=/home/xxxxxx/Music
media_dir=/home/xxxxxx/Music2
media_dir=/home/xxxxxx/Videos
media_dir=/home/xxxxxx/abcde
#
media_dir=/home/xxxxxx/Pictures
media_dir=/home/xxxxxx/Pics
#
media_dir=/home/xxxxxx/Videos/BBC_iPlayer
media_dir=/home/xxxxxx/Videos/BBC_iPlayer/Undercover
media_dir=/home/xxxxxx/Videos/Les_Miserables
media_dir=/home/xxxxxx/Videos/War_and_Peace
media_dir=/home/xxxxxx/Pictures/Holidays/Botswana_&_Hermanus/Hermanus_Videos
media_dir=/home/xxxxxx/Pictures/Holidays/Galapagos/Galapagos_Videos
#
#media_dir=/var/lib/minidlna
#
# Path to the directory that should hold the database and album art cache.
#db_dir=/var/cache/minidlna
#
# Path to the directory that should hold the log file.
#log_dir=/var/log
#
# Type and minimum level of importance of messages to be logged.
#
# The types are "artwork", "database", "general", "http", "inotify",
# "metadata", "scanner", "ssdp" and "tivo".
#
# The levels are "off", "fatal", "error", "warn", "info" or "debug".
# "off" turns of logging entirely, "fatal" is the highest level of importance
# and "debug" the lowest.
log_level=fatal
#
# The types are comma-separated, followed by an equal sign ("="), followed by a
# level that applies to the preceding types. This can be repeated, separating
# each of these constructs with a comma.
#
# The default is to log all types of messages at the "warn" level.
#log_level=general,artwork,database,inotify,scanner,metadata,http,ssdp,tivo=warn
#
# Use a different container as the root of the directory tree presented to
# clients. The possible values are:
#   * "." - standard container
#   * "B" - "Browse Directory"
#   * "M" - "Music"
#   * "P" - "Pictures"
#   * "V" - "Video"
# If you specify "B" and the client device is audio-only then "Music/Folders"
# will be used as root.
#root_container=.
#
# Network interface(s) to bind to (e.g. eth0), comma delimited.
# This option can be specified more than once.
#network_interface=
#
# IPv4 address to listen on (e.g. 192.0.2.1/24).
# If omitted, the mask defaults to 24. The IPs are added to those determined
# from the network_interface option above.
# This option can be specified more than once.
#listening_ip=
#
# Port number for HTTP traffic (descriptions, SOAP, media transfer).
# This option is mandatory (or it must be specified on the command-line using
# "-p").
port=8200
#
# URL presented to clients (e.g. http://example.com:80).
#presentation_url=/
#
# Name that the DLNA server presents to clients.
# Defaults to "hostname: username".
#friendly_name=
#
# Serial number the server reports to clients.
# Defaults to 00000000.
serial=681019810597110
#
# Model name the server reports to clients.
#model_name=Windows Media Connect compatible (MiniDLNA)
#
# Model number the server reports to clients.
# Defaults to the version number of minidlna.
#model_number=
#
# Automatic discovery of new files in the media_dir directory.
inotify=yes
#
# List of file names to look for when searching for album art.
# Names should be delimited with a forward slash ("/").
# This option can be specified more than once.
album_art_names=Cover.jpg/cover.jpg/AlbumArtSmall.jpg/albumartsmall.jpg
album_art_names=AlbumArt.jpg/albumart.jpg/Album.jpg/album.jpg
album_art_names=Folder.jpg/folder.jpg/Thumb.jpg/thumb.jpg
#
# Strictly adhere to DLNA standards.
# This allows server-side downscaling of very large JPEG images, which may
# decrease JPEG serving performance on (at least) Sony DLNA products.
#strict_dlna=no
#
# Support for streaming .jpg and .mp3 files to a TiVo supporting HMO.
#enable_tivo=no
#
# Notify interval, in seconds.
notify_interval=900
#
# Path to the MiniSSDPd socket, for MiniSSDPd support.
#minissdpdsocket=/run/minissdpd.sock

[MickSulley]

ajgreeny, I've just compared my config file with yours -
I have 4 media_dir= entries, you have 12
you have log_level=fatal, I have nothing for that
I have notify_interval=900, you have that line commented out

SeijiSensei, library sizes
Pictures - 20k items 130GB
Music - 25k items 143GB
Video - 2 libraries - 20 items 16.7 GB and 6k items 105 GB

It has been running for a few days now, could it still be indexing?
Thanks
Mick

[SeijiSensei]

Hmm. I have one directory with 2.2 terabytes of content, and three others that total a little over 100 GB.

Something certainly seems wrong.

Try setting "log_level=debug" in /etc/minidlna.conf then rerun the indexer with

sudo minidlnad -R

My logs have lots of warnings, but I don't have problems watching those files. Maybe just include one of the smaller directories to see what happens.

[MickSulley]

Sorry for the delay in replying, I have been testing out many scenarios. Now I am totally confused!!

Following your advice I set the log level and just enabled the smallest directory, restarted etc, and could not see it in top as it was so low. I then added the others in one by one and checked top, showed 100% for a few seconds then dropped. I now have them all enabled again and have just taken out the log_level=debug, so I believe exactly as it was before, and minidlnad shows in top occasionally at around 0.3% CPU.

That was the good news.

However- on my TV I can't see any of them. I can see the server but if I select anything it cannot open the folder to see the actual media. I have tried just enabling a single directory, I did get it to work with just pictures but then tried videos, that didn't work and now pictures won't work either. I removed and purged minidlna and then reinstalled, then edited the config to point to my directories and still it doesn't work. The really odd thing is that on TV I can see my second video directory and the files within but non of them play, and bizarrely I didn't actually enter that directory in the config - how can that happen?

Any ideas? I think I must be missing something really obvious.

Mick

[ajgreeny]

If you look carefully you will see that I have the notify interval 900 the same as you, ie, notify_interval=900, though in may case the line has become separated from the
# Automatic discovery of new files in the media_dir directory.
inotify=yes
lines in the file, probably by my editing.
That should make no difference nor have anything to do with your problem.

Can you check that you are in the minidlna user group and also that user minidlna is in your usergroup; I made that change to make sure no permissions problems followed but I'm not sure if such potential problems would affect the CPU usage as you're seeing.

Finally can you check permissions and file-types for the contents of the folder that will not play, and if necessary change them to:
Owner rw
Group r
Others r
In octal permissions language that is 644 for files, 755 for folders.