tests/rm/ext3-perf.sh

   1 #!/bin/sh
   2 # ensure that "rm -rf DIR-with-many-entries" is not O(N^2)
   3
   4 # Copyright (C) 2008-2018 Free Software Foundation, Inc.
   5
   6 # This program is free software: you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation, either version 3 of the License, or
   9 # (at your option) any later version.
  10
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15
  16 # You should have received a copy of the GNU General Public License
  17 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
  18
  19 . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
  20 print_ver_ rm
  21
  22 very_expensive_
  23
  24 # Using rm -rf to remove a 400k-entry directory takes:
  25 # - 9 seconds with the patch, on a 2-yr-old system
  26 # - 350 seconds without the patch, on a high-end system (disk 20-30% faster)
  27 threshold_seconds=60
  28
  29 # The number of entries in our test directory.
  30 n=400000
  31
  32 # Choose a value that is large enough to ensure an accidentally
  33 # regressed rm would require much longer than $threshold_seconds to remove
  34 # the directory.  With n=400k, pre-patch GNU rm would require about 350
  35 # seconds even on a fast disk.  On a relatively modern system, the
  36 # patched version of rm requires about 10 seconds, so even if you
  37 # choose to enable very expensive tests with a disk that is much slower,
  38 # the test should still succeed.
  39
  40 # Skip unless "." is on an ext[34] file system.
  41 # FIXME-maybe: try to find a suitable file system or allow
  42 # the user to specify it via an envvar.
  43 df -T -t ext3 -t ext4dev -t ext4 . \
  44   || skip_ 'this test runs only on an ext3 or ext4 file system'
  45
  46 # Skip if there are too few inodes free.  Require some slack.
  47 free_inodes=$(stat -f --format=%d .) || framework_failure_
  48 min_free_inodes=$(expr 12 \* $n / 10)
  49 test $min_free_inodes -lt $free_inodes \
  50   || skip_ "too few free inodes on '.': $free_inodes;" \
  51       "this test requires at least $min_free_inodes"
  52
  53 ok=0
  54 start=$(date +%s)
  55 mkdir d &&
  56   cd d &&
  57     seq $n | xargs touch &&
  58     test -f 1 &&
  59     test -f $n &&
  60   cd .. &&
  61   ok=1
  62 test $ok = 1 || framework_failure_
  63 setup_duration=$(expr $(date +%s) - $start)
  64 echo creating a $n-entry directory took $setup_duration seconds
  65
  66 # If set-up took longer than the default $threshold_seconds,
  67 # use the longer set-up duration as the limit.
  68 test $threshold_seconds -lt $setup_duration \
  69   && threshold_seconds=$setup_duration
  70
  71 start=$(date +%s)
  72 timeout ${threshold_seconds}s rm -rf d; err=$?
  73 duration=$(expr $(date +%s) - $start)
  74
  75 case $err in
  76   124) fail=1; echo rm took longer than $threshold_seconds seconds;;
  77   0) ;;
  78   *) fail=1;;
  79 esac
  80
  81 echo removing a $n-entry directory took $duration seconds
  82
  83 Exit $fail