nixpkgs/pkgs/tools/system/swaplist/default.nix

   1 { coreutils
   2 , stdenv
   3 , writeShellScriptBin
   4 }:
   5 let PATH = stdenv.lib.concatStringsSep ":" [ "${coreutils}/bin" ];
   6 in
   7 writeShellScriptBin "swaplist" ''
   8   # SYNTAX:
   9   # DESCRIPTION: print sorted swap usage of processes using it
  10   export PATH=${PATH}
  11   lastpid=
  12   swap=0
  13   sudo grep -H '^Swap:' /proc/*/smaps 2>/dev/null |
  14   while IFS=: read -r file x size x
  15    do
  16           pid=''${file#/proc/}
  17           pid=''${pid%/smaps}
  18           size=''${size% kB}
  19           size=''${size##* }
  20           if test "$pid" = "$lastpid"
  21            then swap=$(( swap + size ))
  22            else
  23                   if test "$swap" -gt 0
  24                    then printf "%u pid=%u cmd=%s\n" "$swap" "$lastpid" "$(tr '\000' ' ' </proc/"$lastpid"/cmdline)"
  25                    fi
  26                   if test "$pid" = self
  27                    then break
  28                    else
  29                           lastpid=$pid
  30                           swap=$size
  31                    fi
  32            fi
  33    done |
  34   sort -nk1,1
  35 ''