input_cache behaivor

[ilyxa]

Question

What is planned input_cache behaivor?

Later mpd (git, 0.22r417.g44aaf5134, aarch64) was installed:

[root@kangaroo ~]# mpd -V | head -1
Music Player Daemon 0.22~git (v0.21.10-417-g44aaf5134)

Added few config lines:

input_cache {
        size "256 MB"
}

Files located on NFS share (music_directory "nfs://snooky/storarray/nas/music"). Database is remote.
Running:

root@kangaroo ~]# mpc 
lossless/Eagles - Hotel California  1976/01 - Hotel California.flac
[playing] #1/9   1:26/6:30 (22%)
volume:100%   repeat: off   random: off   single: off   consume: off
[root@kangaroo ~]# ps Hh -p `pidof -s mpd` -o 'pid,tid,class,priority,comm,s,pcpu,vsize,drs'
 1023  1023 TS   20 mpd             S  9.8 614744 613105
 1023  1024 TS   20 io              S  5.6 614744 613105
 1023  1025 FF  -51 rtio            S  0.1 614744 613105
 1023  1026 TS   20 player          S  0.5 614744 613105
 1023  1027 TS   20 decoder:flac    S  4.2 614744 613105
 1023  1028 FF  -51 output:FX-Audio R  7.2 614744 613105
 1023  1031 TS   20 output:FX-Audio R 11.0 614744 613105
 1023  1032 TS   20 output:FX-Audio R  9.3 614744 613105
 1023  1033 TS   20 output:FX-Audio R  8.6 614744 613105
[root@kangaroo ~]# 

Memory consumption is static, enough free memory is available:

[root@kangaroo ~]# free
              total        used        free      shared  buff/cache   available
Mem:         924264       77900      674296         300      172068      831340
Swap:             0           0           0

My expectation was that this will be some kind of in-memory buffer (512 MB, sort of, used memory).

PS:
Stable mpd (0.21 branch) memory consumption:

[root@kangaroo ~]# ps Hh -p `pidof -s mpd` -o 'pid,tid,class,priority,comm,s,pcpu,vsize,drs'
  905   905 TS   20 mpd             S  5.5 614540 612822
  905   906 TS   20 io              R  3.9 614540 612822
  905   907 FF  -51 rtio            S  0.1 614540 612822
  905   909 TS   20 player          R  0.4 614540 612822
  905   910 TS   20 decoder:flac    S  4.4 614540 612822
  905   915 FF  -51 output:FX-Audio R 12.1 614540 612822
  905   916 TS   20 output:FX-Audio R 11.3 614540 612822
  905   917 TS   20 output:FX-Audio R 10.7 614540 612822
  905   918 TS   20 output:FX-Audio R  8.8 614540 612822

Very near the same (kb doesn't matter).

[MaxKellermann]

Right now, it caches only local files, and is extremely clumsy about it. This feature is in early development, and needs lots of time & love.

[ilyxa]

[ilyxa@wombat ~]$ ps Hh -p `pidof -s mpd` -o 'pid,tid,uid,class,priority,comm,s,pcpu,vsize,drs'
 4583  4583     0 TS   20 mpd             S 11.0 889544 889544
 4583  4584     0 TS   20 io              S  0.0 889544 889544
 4583  4585     0 FF  -51 rtio            S  1.0 889544 889544
 4583  4586     0 TS   20 player          S  0.0 889544 889544
 4583  4587     0 TS   20 decoder:flac    S  3.5 889544 889544
 4583  4588     0 TS   20 buffering       D 20.5 889544 889544
 4583  4589     0 FF  -51 output:DSD1796  S  0.0 889544 889544
 4583  4590     0 FF  -51 output:int audi S  5.0 889544 889544

got it ;)