---
- branch: MAIN
  date: Sat Jul 24 13:42:05 UTC 2021
  files:
  - new: '1.89'
    old: '1.88'
    path: src/usr.bin/systat/vmstat.c
    pathrev: src/usr.bin/systat/vmstat.c@1.89
    type: modified
  id: 20210724T134205Z.5995fc14eff308af1936096ecdc28c6700ff1bdf
  log: |
    Instead of getting an estimate of the number of kernel buffers,
    allocating memory for them, requesting all the metadata contents of
    these buffers (and repeating in the unlikely case of the number of
    buffers increasing too much since the estimate) and then straight away
    throwing all the contents out just to count how many buffers there were,
    just get the initial estimate from the kernel and subtract the slop.

    Reduces system CPU usage of "systat vm" by approx 80% for any system
    with a reasonable number of buffers.
  module: src
  subject: 'CVS commit: src/usr.bin/systat'
  unixtime: '1627134125'
  user: simonb