Vestat

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The /proc/vz/vestat file contains statistics for VE CPU usage.

The guessed content (may the Gods - blessed thy fingers - acknowledge or reject my humble info here) ( See http://forum.openvz.org/index.php?t=msg&goto=2687 (OpenVZ developer talks /proc/vz/vestat) for more info):

  • VEID: The VE ID, obviously.
  • user, nice, system, uptime: usage in jiffies. These are the equivalents of /proc/stat, but there is no idle because it cannot be measured this way.
  • idle, strv, uptime, used: usage in cycles. idle and uptime are obvious, strv isn't used, and used is the used cycles by VE on all CPUs.
  • maxlat, totlat, numsched: latency statistics in cycles. maxlat is max latency in cycles meaning how long VE process has to wait before it actually got CPU time; totlat/numsched gives average scheduling latency. These do not seem work in OpenVZ, only in Virtuozzo.

Measure conversions[edit]

Using jiffies:

  • seconds = measurement / jiffies_per_seconds

Using cycles:

  • seconds = measurement / frequency_of_your_cpu

Variables:

  • jiffies_per_second = 1000 (more often 100, unless you have changed that in kernel config, check CONFIG_HZ= in kernel .config or /proc/config.gz)
  • cycles_per_jiffy = frequency_of_your_cpu / jiffies_per_second
  • frequency_of_your_cpu (in Hz) can be read from /proc/cpuinfo, as:
    • cpu MHz : megahertz, and thus frequency_of_your_cpu = megahertz * 1048576 (for multiCPU machines this is based on the speed of one cpu only)