timer entropy daemon

This program feeds the /dev/random device with entropy-data (random values) read from timers.
It does this by measuring how much longer or shorter a sleep takes (this fluctuates a little - microseconds). The time for a sleep jitters due to that the frequency of the clocks of the timers change when they become colder or hotter (and a few other parameters).
This program does not require any extra hardware.
It produces around 500 bits per second.
This program is also usable with virtualized systems (KVM has virtio-rnd, you can then still use this program on the host).


Latest stable release:timer_entropyd-0.2.tgz


0.2: applied patch by Alexander Clouter which makes it only process the timer when the kernel entropy buffer is empty enough
0.1: initial release


  • VideoEntropyd is like timer-entropyd for a 'video-4-linux'-compatible device. E.g. a tv-card or a webcam.
  • AudioEntropyd is like timer-entropyd for a ALSA-compatible audio-device.


Not every system produces the same amount of bits per second.
Please note: bps is bits per second, not bytes.
motherboard or systemprocessorclockspeedbps
Intel DG965WHIntel Q66002.4GHz2268
Asus P5K WSIntel E66002.4GHz358
Gigabyte 965G-DS3Intel Q94502.66GHz1751
Via Nehemiah C3530MHz2442 (*1)
Via C71.8GHz1491 (*1)
PhoenixAMD Athlon XP1.6GHz43024
ASUS A8N-EAMD Athlon 64 X2 4200+2.3GHz117
ASUS M3AAMD Athlon 64 X2 4800+2.6GHz112
Via TUV4X Tualatin Celeron III800 Mhz2447
IBM xSeries 330 8654-52GP3 Coppermine1GHz4440
IBM x3800 8865-2RGIntel Xeon3.6GHz3238
IBM 9113-550Power5 (in an LPAR)1.5GHz23
SGI O200 (running IRIX)MIPS R12000270MHz191
PowerEdge R200 (running FreeBSD)Intel Xeon CPU 30652.3GHz189
VMware Workstation on lenovo t61i386 emulation2.4GHz245
*1: has an integrated rng as well

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