proclimit.sh

#!/usr/bin/env sh

##
# When this script is invoked inside of a zone:
#
# This script returns a number representing a very conservative estimate of the
# maximum number of processes or threads that you want to run within the zone
# that invoked this script. Typically, you would take this value and define a
# multiplier that works well for your application.
#
# Otherwise:
# This script returns the number of cores reported by the OS.

# If we are on a LX Brand Zone calculation value using utilities only available in the /native
# directory

if [ -d /native ]; then
  PATH=$PATH:/native/sbin:/native/usr/bin:/native/sbin
fi

KSH="$(which ksh93)"
PRCTL="$(which prctl)"

if [ -n "${KSH}" ] && [ -n "${PRCTL}" ]; then
  CAP=$(${KSH} -c "echo \$((\$(${PRCTL} -n zone.cpu-cap -P \$\$ | grep privileged | awk '{ print \$3; }') / 100))")

  # Always show at least one processor
  if [ ${CAP} -lt 1 ]; then
    echo 1
    exit 0
  fi

  # If there is no cap set, then we will fall through and use the other functions
  # to determine the maximum processes.
  if [ -n "${CAP}" ]; then
    $KSH -c "echo \$((ceil(${CAP})))"
    exit 0
  fi
fi

# Linux calculation if you have nproc
if [ -n "$(which nproc)" ]; then
  nproc
  exit 0
fi

# Linux more widely supported implementation
if [ -f /proc/cpuinfo ] && [ -n $(which wc) ]; then
  grep processor /proc/cpuinfo | wc -l
  exit 0
fi

# OS X calculation
if [ "$(uname)" == "Darwin" ]; then
  sysctl -n hw.ncpu
  exit 0
fi

# Fallback value if we can't calculate
echo 1