Performance

Performance

Tests of OWFS 2.5p7

Details, owfs listing of uncached directory:

> time for x in 0 1 2 3 4 5 6 7 8 9 ; do ls /mnt/1wire/uncached ; done 

Directory has 111 1-wire devices, from family code 01 to 89.

01.0683C9090000  10.164F54000800  10.42916B000800  10.611154000800  10.894F54000800  10.A73A54000800  10.C44154000800  10.E04654000800  10.FA1E54000800  2C.8EF604000000
01.4FA8CC080000  10.182654000800  10.483354000800  10.641654000800  10.8B3954000800  10.AA4D54000800  10.C64354000800  10.E12954000800  10.FC2154000800  89.852BC300705E
01.5F50CA090000  10.1D1554000800  10.4A2D54000800  10.653E54000800  10.904154000800  10.AC2754000800  10.C74E54000800  10.EB1254000800  10.FD1D54000800  89.BD29C300705E
05.5ADD1E000000  10.234254000800  10.4A4454000800  10.674E54000800  10.904954000800  10.AD1A54000800  10.CE4B54000800  10.ED3554000800  12.15DF1F000000  alarm
05.DD011F000000  10.2C1B54000800  10.4E4C54000800  10.6F3F54000800  10.974F54000800  10.B14154000800  10.CF1F54000800  10.EF2E54000800  12.4AE41F000000  bus.0
10.003054000800  10.2D4154000800  10.552954000800  10.711C54000800  10.9A2F54000800  10.B64054000800  10.D03754000800  10.F03D54000800  12.C4DF1F000000  simultaneous
10.044954000800  10.301A54000800  10.584E54000800  10.792F54000800  10.9A9E3C000800  10.B72E54000800  10.D54B54000800  10.F12254000800  12.F3EA1F000000
10.052854000800  10.311154000800  10.5A3F54000800  10.793E54000800  10.9B2D54000800  10.B74754000800  10.D7AB3C000800  10.F12754000800  22.018503000000
10.074D54000800  10.39756B000800  10.5E1B54000800  10.7E3754000800  10.9C4654000800  10.B83754000800  10.DA4754000800  10.F43054000800  22.367A03000000
10.0D2B54000800  10.3C1F54000800  10.601454000800  10.801754000800  10.9D4154000800  10.BB1754000800  10.DB2754000800  10.F84C54000800  28.EB6731000000
10.101454000800  10.401D54000800  10.602454000800  10.821454000800  10.A44E54000800  10.BE2254000800  10.DC3D54000800  10.F8866B000800  2C.1B7900000000
10.101554000800  10.414354000800  10.602E54000800  10.892254000800  10.A53654000800  10.C24654000800  10.DC4454000800  10.F93D54000800  2C.66FE04000000

Times are for each pass through 111 devices. 

 

Adapter  Bus elapsed time user system per entry
DS9097 (passive)   serial  59.83  0.0016 0.0016 0.539
DS9097U  serial   9.91 0.0020 0.0016 0.088
LINK (emulation mode)  serial   9.86 0.0020 0.0020 0.089
LINK (ascii mode)  serial   6.71 0.0024 0.0012 0.060
DS9490R  usb   2.22 0.0004 0.0036 0.020
           
           

 

Notes:

  • All adapters except the "Passive" and LINK add an extra device embedded in the adapter. "Per entry" uses 112 as the denominator in those cases.
  • The USB adapter was the least tolerant of a bad network design, dropping 6 devices in one pass.
  • Tests done on an AMD64 machine in 64 bit mode. Linux 2.6 kernel.

Comclusions:

  • Bit-banging (Passive adapter) is particularly slow in modern operating systems.
  • The LINK is indistiguishable from the DS9097U in emulation mode.
  • The LINK's ascii mode is well suited to directory listings.