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dolohow / uksm

Ultra Kernel Samepage Merging
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Total number of frames #74

Open gaulthiergain opened 2 years ago

gaulthiergain commented 2 years ago

In order to compute the total number of frames, I did the following computation with KSM vanilla:

#used_frames = pages_volatile+pages_unshared+pages_shared

Is this calculation still valid with uksm? (not considering volatile pages):

#used_frames = pages_unshared+pages_shared

dolohow commented 2 years ago

This is my script written in fish that does the calculation

function uksm_profit
  if not test -d /sys/kernel/mm/uksm
    echo "UKSM not installed"
    return
  end
  set pages (cat /sys/kernel/mm/uksm/pages_sharing)
  set zero_pages (cat /proc/meminfo | grep KsmZero | awk '{print $2}')

  set total_in_MB (echo "scale=2; $pages*4/1024 + $zero_pages/1024" | bc)

  printf "Saved %s MB\n" $total_in_MB
end

You also need to take into account zero pages, which are handled by UKSM separately.