src/fill2fs - pub/scm/linux/kernel/git/jlayton/xfstests-dev - Git at Google

 #!/usr/bin/perl -w
 #
 #  Copyright (c) 2000-2001 Silicon Graphics, Inc.  All Rights Reserved.
 #
 # fill2fs:
 #   Fill a filesystem, or write a specified number of bits.
 #   Script runs deterministically given a seed for the random number
 #   generator. Will generate the same set of directories and files,
 #   with the only source of variation the precise point at which the
 #   filesystem fills up. When used with XFS filesystems, and when
 #   the filesize is small, XFS pre-allocation may cause the filesystem
 #   to "fill up" before the actual disk space is gone. Using this
 #   script repeatedly, with a delay between invocations, to account
 #   for extent flushing, will allow more of the filesystem to be filled.
 #
 #   All generated files are checksummed and this sum is stored in the
 #   filename (files are named: <sequence number>.<checksum>.data.
 #   Normally script is invoked using the --list option, which causes all
 #   data files to be written to standard output (--list=-) or a file
 #   (--list=filename). This list can be fed into fill2fs_check, which
 #   recomputes the checksums and flags any errors.
 #
 #   The --stddev=0 forces all files to be precisely --filesize bytes in
 #   length, some other value (--stddev=val) produces filesizes with a
 #   normal distribution with standard deviation val. If not specified
 #   most file sizes are set to lie within 30% of the requested file size.
 #
 #   fill2fs is not guaranteed to write the requested number of bytes, or
 #   fill the filesystem completely. However, it and fill2 are both very
 #   careful about establishing when write operations fail. When the
 #   --verbose option is used the number of bytes "actually written"
 #   is guaranteed to be the number of bytes on disk.
 #
 #   $Id$
 #

 use Getopt::Long;
 use File::Basename;

 chomp($os = `uname`);

 #
 # fsinfo: get filesystem info put it into the global namespace, initialises:
 #	$dev, $type, $blocks, $used, $avail, $cap, $mnt, $mnt_options
 #	$fsblocks, $fsblocksize, $agblocks, $agcount, $imax_pct, $logblocks
 #	$logstart, $internal
 #
 # if $verbose is set then output fs info to STDERR
 #

 sub fsinfo {
   my($file) = $_[0];

   # filesystem space and mount point

   $cmd = "df" if ($os =~ /IRIX/);
   $cmd = "df -P -T --block-size=512" if ($os =~ /Linux/);
   chomp($_ = `$cmd $file | tail -1`);
   $n = ($dev, $type, $blocks, $used, $avail, $cap, $mnt) = split(/ +/);
   die("df failed") if ($n != 7);

   if ($fscheck && $type ne "xfs") {
     die("Error: $progname: filesystem is not xfs")
   }

   # how was this filesystem mounted
   $_ = `grep $dev /etc/mtab`;
   @mtab = split(/ +/);
   $mnt_options = $mtab[3];

   # if we're running as root run xfs_db on the filesystem
   if ($> == 0) {
     # xfs_db: read only, use the default superblock, print everything
     die("Error: $progname: can't read device: \"$dev\"\n") if (! -r $dev);
     $_=`xfs_db -r -c sb -c p $dev`;
     # multiline matching ^$ refers to individual lines...
     ($fsblocks) = /^dblocks = (\d+)$/m;
     ($fsblocksize) = /^blocksize = (\d+)$/m;
     ($agblocks) = /^agblocks = (\d+)$/m;
     ($agcount) = /^agcount = (\d+)$/m;
     ($imax_pct) = /^imax_pct = (\d+)$/m;
     ($logblocks) = /^logblocks = (\d+)$/m;
     ($logstart) = /^logstart = (\d+)$/m;
     $internal = $logstart > 0 ? " (internal)" : "";

     $verbose && print STDERR <<"EOF"
 Filesystem information:
   type=$type; device=$dev
   mount point=$mnt; mount options=$mnt_options
   percent full=$cap; size (512 byte blocks)=$blocks; used=$used; avail=$avail
   total filesystem size (fs blocks)=$fsblocks; fs block size=$fsblocksize; imax_pct=$imax_pct
   agcount=$agcount; agblocks=$agblocks; logblocks=$logblocks; logstart=$logstart$internal
 EOF
   }
 }


 # returns numbers with a normal distribution
 sub normal {
   my($mean) = $_[0];
   my($stddev) = $_[1];

   $x = -6.0;
   for ($i = 0; $i < 12; $i++) {
     $x += rand;
   }

   $x = $mean + $stddev * $x;
   return $x;
 }

 #
 # determine script location and find fill2
 #

 chomp($cwd = `pwd`);
 chomp($_ = `which fill2 2>&1 | head -1`);
 if (-x $_) {
   # look in the path
   $fill2 = fill2;
 }
 else {
   # in the same directory - get absolute path
   chomp($dirname = dirname $0);
   if ($dirname =~ m!^/.*!) {
     $fill2 = $dirname . "/fill2";
   }
   else {
     # relative
     $fill2 = $cwd . "/" . $dirname . "/fill2";
   }
   if (! -x $fill2) {
     die("Error: $progname: can't find fill2, tried \"$fill2\"\n");
   }
 }

 #
 # process/check args
 #

 $progname=$0;
 GetOptions("bytes=f" => \$bytes,
 	   "dir=s" => \$root,
 	   "filesize=i" => \$filesize,
 	   "force!" => \$force,
 	   "help!" => \$help,
 	   "list=s" => \$list,
 	   "fscheck!" => \$fscheck,
 	   "percent=f" => \$percentage,
 	   "seed=i" => \$seed,
 	   "stddev=i" => \$stddev,
 	   "sync=i" => \$sync_bytes,
 	   "verbose!" => \$verbose);


 # check/remove output directory, get filesystem info
 if (defined $help
     || (! defined $root && @ARGV != 1)
     || (defined $root && @ARGV == 1))
 {
   # newline at end of die message suppresses line number
   print STDERR <<"EOF";
 Usage: $progname [options] root_dir
 Options:
   --bytes=num       total number of bytes to write
   --dir=name        where to write files
   --filesize=num    set all files to num bytes in size
   --force           overwrite any existing files
   --help            print this help message
   --list=filename   store created files to filename (- for stdout)
   --percent=num     percentage of filesystem to fill
   --seed=num        seed for random number generator
   --stddev          set file size standard deviation
   --sync=num	    sync every num bytes written
   --verbose         verbose output
 EOF
   exit(1) unless defined $help;
   # otherwise...
   exit(0);

 }


 #
 # lots of boring argument checking
 #

 # root directory and filesystem info
 $root = $ARGV[0] if (@ARGV == 1);
 if (-e $root) {
   if (! $force) {
     die("Error: $progname: \"$root\" already exists\n");
   }
   else {
     $verbose && print STDERR "Removing \"$root\"... ";
     system("rm -rf $root");
     $verbose && print STDERR "done\n";
   }
 }
 chomp($root_dir = dirname $root);
 fsinfo $root_dir;

 # $list can be "-" for stdout, perl open ">-" opens stdout
 open LIST, ">$list" if (defined $list);

 # how many bytes should we write
 if (defined $bytes && defined $percentage) {
   die("Error: $progname: can't specify --bytes and --percent\n");
 }
 # check percentage
 if (defined $percentage && ($percentage < 0 || $percentage > 100)) {
   die("Error: $progname: invalid percentage\n");
 }
 if (! defined $bytes && ! defined $percentage) {
   $bytes = $avail * 512;
   $verbose && print STDERR <<"EOF";
 Neither --bytes nor --percent specified: filling filesystem ($bytes bytes)
 EOF
 }
 elsif (! defined $bytes) {
   $bytes = int($blocks * 512 * $percentage / 100.0);
 }
 if (($bytes > $blocks * 512) || (! $force && $bytes > $avail * 512))
 {
   die("Error: $progname: not enough free disk space, disk is $cap full\n");
 }


 #
 # To get fix sized files set stddev to 0. The default is to make most files
 # within 30% of the requested filesize (or 4k if filesize is not specified).
 # Set the standard deviation to be half of the required percentage: ~95% of
 # samples lie within 2 standard deviations of the mean.
 #

 $filesize = 4096 if (! defined $filesize);
 die("Error: $progname: --filesize must be >= 1 byte") if ($filesize < 1);
 $stddev = 0.5 * 0.3 * $filesize if (! defined $stddev);
 $seed = time ^ $$ if (! defined $seed);
 srand $seed;
 umask 0000;
 mkdir $root, 0777;
 chdir $root;
 $total = 0;
 $files = 0;
 $dirs = 0;
 $d = 0;
 $sync_cnt = 1;

 #
 # fill filesystem
 #

 $verbose && print STDERR "Writing $bytes bytes (seed is $seed)... ";
 while ($total < $bytes) {
   $r = rand(3.0);

   if (($d == 0 && $r < 0.5) || ($d > 0 && $r >= 0.0 && $r < 2.4)) {
     # create a new data file
     $n = sprintf("%04d", $names[$d]++);
     if ($stddev == 0) {
       $size = $filesize;
     }
     else {
       $size = int(normal($filesize, $stddev));
     }
     $left = $bytes - $total;
     $size = 0 if ($size < 0);
     $size = $left if ($size > $left);

     # fill2 will fail if the filesystem is full - not an error!
     $cmd = "$fill2 -d nbytes=$size,linelength=72,seed=$n -b 4k $n";
     $cmd .= " > /dev/null 2>&1" if (! $verbose);
     if (system($cmd) != 0) {
       if ($verbose) {
 	warn("can't create a file - assuming filesystem is full\n");
       }
       if (-e $n && unlink($n) != 1) {
 	warn("couldn't delete \"$n\"");
       }
       last;
     }
     $_ = `sum -r $n`;
     ($sum) = split(/ +/);
     $name = "$n.$sum.data";
     $cmd = "mv $n $name";	# perl rename failed earlier than using mv
     $cmd .= " > /dev/null 2>&1" if (! $verbose);
     if (system($cmd) != 0) {
       if ($verbose) {
 	warn("can't rename a file - assuming filesystem is full\n");
       }
       if (-e $name && unlink($name) != 1) {
 	warn("couldn't delete \"$name\"");
       }
       last;
     }
     if (defined $list) {
       chomp($_ = `pwd`);
       printf LIST ("%s/%s\n", $_, $name);
     }
     $total += $size;
     $files++;

     if (defined $sync_bytes && int($total / $sync_bytes) > $sync_cnt) {
       $sync_cnt++;
       system("sync");
     }
   }
   # note that if d==0 create directories more frequently than files
   elsif (($d == 0 && $r >= 0.5) || ($d > 0 && $r >= 2.4 && $r < 2.7)) {
     # create a new directory and descend
     $name = sprintf("%04d.d", $names[$d]++);
     if (! mkdir($name, 0777)) {
       warn("can't make a directory - assuming filesystem is full\n");
       last;
     }
     chdir($name) or die();
     $d++;
     $dirs++;
   }
   elsif ($r >= 2.7 && $r < 3.0) {
     # pop up to the parent directory same probability as descend
     die("Error: $progname: panic: shouldn't be here!") if ($d == 0);
     chdir("..") or die();
     $d--;
   }
 }
 # make sure we return to the original working directory
 chdir($cwd) or die();
 $verbose && print STDERR "done\n";
 $verbose && print STDERR "$total bytes (in $files files and $dirs directories) were actually written\n";
 close LIST;
 exit(0) if ($total = $bytes);
 exit(1) if ($total == 0);
 exit(2) if ($total > 0 && $total < $bytes);

 # - to sum all generated data:
 #   find /home/fill/ -name \*data | xargs ls -al | awk '{total = total + $5; } END { printf("total = %d bytes\n", total); }'
 # - to find any files not of the required size
 #   find . -name \*data -a \! -size 4096c
 # - count new files
 #   find ./fill -name \*.data | wc
 # - count new directories
 #   find ./fill -name \*.d | wc
	#!/usr/bin/perl -w
	#
	# Copyright (c) 2000-2001 Silicon Graphics, Inc. All Rights Reserved.
	#
	# fill2fs:
	# Fill a filesystem, or write a specified number of bits.
	# Script runs deterministically given a seed for the random number
	# generator. Will generate the same set of directories and files,
	# with the only source of variation the precise point at which the
	# filesystem fills up. When used with XFS filesystems, and when
	# the filesize is small, XFS pre-allocation may cause the filesystem
	# to "fill up" before the actual disk space is gone. Using this
	# script repeatedly, with a delay between invocations, to account
	# for extent flushing, will allow more of the filesystem to be filled.
	#
	# All generated files are checksummed and this sum is stored in the
	# filename (files are named: <sequence number>.<checksum>.data.
	# Normally script is invoked using the --list option, which causes all
	# data files to be written to standard output (--list=-) or a file
	# (--list=filename). This list can be fed into fill2fs_check, which
	# recomputes the checksums and flags any errors.
	#
	# The --stddev=0 forces all files to be precisely --filesize bytes in
	# length, some other value (--stddev=val) produces filesizes with a
	# normal distribution with standard deviation val. If not specified
	# most file sizes are set to lie within 30% of the requested file size.
	#
	# fill2fs is not guaranteed to write the requested number of bytes, or
	# fill the filesystem completely. However, it and fill2 are both very
	# careful about establishing when write operations fail. When the
	# --verbose option is used the number of bytes "actually written"
	# is guaranteed to be the number of bytes on disk.
	#
	# $Id$
	#

	use Getopt::Long;
	use File::Basename;

	chomp($os = `uname`);

	#
	# fsinfo: get filesystem info put it into the global namespace, initialises:
	# $dev, $type, $blocks, $used, $avail, $cap, $mnt, $mnt_options
	# $fsblocks, $fsblocksize, $agblocks, $agcount, $imax_pct, $logblocks
	# $logstart, $internal
	#
	# if $verbose is set then output fs info to STDERR
	#

	sub fsinfo {
	my($file) = $_[0];

	# filesystem space and mount point

	$cmd = "df" if ($os =~ /IRIX/);
	$cmd = "df -P -T --block-size=512" if ($os =~ /Linux/);
	chomp($_ = `$cmd $file \| tail -1`);
	$n = ($dev, $type, $blocks, $used, $avail, $cap, $mnt) = split(/ +/);
	die("df failed") if ($n != 7);

	if ($fscheck && $type ne "xfs") {
	die("Error: $progname: filesystem is not xfs")
	}

	# how was this filesystem mounted
	$_ = `grep $dev /etc/mtab`;
	@mtab = split(/ +/);
	$mnt_options = $mtab[3];

	# if we're running as root run xfs_db on the filesystem
	if ($> == 0) {
	# xfs_db: read only, use the default superblock, print everything
	die("Error: $progname: can't read device: \"$dev\"\n") if (! -r $dev);
	$_=`xfs_db -r -c sb -c p $dev`;
	# multiline matching ^$ refers to individual lines...
	($fsblocks) = /^dblocks = (\d+)$/m;
	($fsblocksize) = /^blocksize = (\d+)$/m;
	($agblocks) = /^agblocks = (\d+)$/m;
	($agcount) = /^agcount = (\d+)$/m;
	($imax_pct) = /^imax_pct = (\d+)$/m;
	($logblocks) = /^logblocks = (\d+)$/m;
	($logstart) = /^logstart = (\d+)$/m;
	$internal = $logstart > 0 ? " (internal)" : "";

	$verbose && print STDERR <<"EOF"
	Filesystem information:
	type=$type; device=$dev
	mount point=$mnt; mount options=$mnt_options
	percent full=$cap; size (512 byte blocks)=$blocks; used=$used; avail=$avail
	total filesystem size (fs blocks)=$fsblocks; fs block size=$fsblocksize; imax_pct=$imax_pct
	agcount=$agcount; agblocks=$agblocks; logblocks=$logblocks; logstart=$logstart$internal
	EOF
	}
	}


	# returns numbers with a normal distribution
	sub normal {
	my($mean) = $_[0];
	my($stddev) = $_[1];

	$x = -6.0;
	for ($i = 0; $i < 12; $i++) {
	$x += rand;
	}

	$x = $mean + $stddev * $x;
	return $x;
	}

	#
	# determine script location and find fill2
	#

	chomp($cwd = `pwd`);
	chomp($_ = `which fill2 2>&1 \| head -1`);
	if (-x $_) {
	# look in the path
	$fill2 = fill2;
	}
	else {
	# in the same directory - get absolute path
	chomp($dirname = dirname $0);
	if ($dirname =~ m!^/.*!) {
	$fill2 = $dirname . "/fill2";
	}
	else {
	# relative
	$fill2 = $cwd . "/" . $dirname . "/fill2";
	}
	if (! -x $fill2) {
	die("Error: $progname: can't find fill2, tried \"$fill2\"\n");
	}
	}

	#
	# process/check args
	#

	$progname=$0;
	GetOptions("bytes=f" => \$bytes,
	"dir=s" => \$root,
	"filesize=i" => \$filesize,
	"force!" => \$force,
	"help!" => \$help,
	"list=s" => \$list,
	"fscheck!" => \$fscheck,
	"percent=f" => \$percentage,
	"seed=i" => \$seed,
	"stddev=i" => \$stddev,
	"sync=i" => \$sync_bytes,
	"verbose!" => \$verbose);


	# check/remove output directory, get filesystem info
	if (defined $help
	\|\| (! defined $root && @ARGV != 1)
	\|\| (defined $root && @ARGV == 1))
	{
	# newline at end of die message suppresses line number
	print STDERR <<"EOF";
	Usage: $progname [options] root_dir
	Options:
	--bytes=num total number of bytes to write
	--dir=name where to write files
	--filesize=num set all files to num bytes in size
	--force overwrite any existing files
	--help print this help message
	--list=filename store created files to filename (- for stdout)
	--percent=num percentage of filesystem to fill
	--seed=num seed for random number generator
	--stddev set file size standard deviation
	--sync=num sync every num bytes written
	--verbose verbose output
	EOF
	exit(1) unless defined $help;
	# otherwise...
	exit(0);

	}


	#
	# lots of boring argument checking
	#

	# root directory and filesystem info
	$root = $ARGV[0] if (@ARGV == 1);
	if (-e $root) {
	if (! $force) {
	die("Error: $progname: \"$root\" already exists\n");
	}
	else {
	$verbose && print STDERR "Removing \"$root\"... ";
	system("rm -rf $root");
	$verbose && print STDERR "done\n";
	}
	}
	chomp($root_dir = dirname $root);
	fsinfo $root_dir;

	# $list can be "-" for stdout, perl open ">-" opens stdout
	open LIST, ">$list" if (defined $list);

	# how many bytes should we write
	if (defined $bytes && defined $percentage) {
	die("Error: $progname: can't specify --bytes and --percent\n");
	}
	# check percentage
	if (defined $percentage && ($percentage < 0 \|\| $percentage > 100)) {
	die("Error: $progname: invalid percentage\n");
	}
	if (! defined $bytes && ! defined $percentage) {
	$bytes = $avail * 512;
	$verbose && print STDERR <<"EOF";
	Neither --bytes nor --percent specified: filling filesystem ($bytes bytes)
	EOF
	}
	elsif (! defined $bytes) {
	$bytes = int($blocks * 512 * $percentage / 100.0);
	}
	if (($bytes > $blocks * 512) \|\| (! $force && $bytes > $avail * 512))
	{
	die("Error: $progname: not enough free disk space, disk is $cap full\n");
	}



	#
	# To get fix sized files set stddev to 0. The default is to make most files
	# within 30% of the requested filesize (or 4k if filesize is not specified).
	# Set the standard deviation to be half of the required percentage: ~95% of
	# samples lie within 2 standard deviations of the mean.
	#

	$filesize = 4096 if (! defined $filesize);
	die("Error: $progname: --filesize must be >= 1 byte") if ($filesize < 1);
	$stddev = 0.5 * 0.3 * $filesize if (! defined $stddev);
	$seed = time ^ $$ if (! defined $seed);
	srand $seed;
	umask 0000;
	mkdir $root, 0777;
	chdir $root;
	$total = 0;
	$files = 0;
	$dirs = 0;
	$d = 0;
	$sync_cnt = 1;

	#
	# fill filesystem
	#

	$verbose && print STDERR "Writing $bytes bytes (seed is $seed)... ";
	while ($total < $bytes) {
	$r = rand(3.0);

	if (($d == 0 && $r < 0.5) \|\| ($d > 0 && $r >= 0.0 && $r < 2.4)) {
	# create a new data file
	$n = sprintf("%04d", $names[$d]++);
	if ($stddev == 0) {
	$size = $filesize;
	}
	else {
	$size = int(normal($filesize, $stddev));
	}
	$left = $bytes - $total;
	$size = 0 if ($size < 0);
	$size = $left if ($size > $left);

	# fill2 will fail if the filesystem is full - not an error!
	$cmd = "$fill2 -d nbytes=$size,linelength=72,seed=$n -b 4k $n";
	$cmd .= " > /dev/null 2>&1" if (! $verbose);
	if (system($cmd) != 0) {
	if ($verbose) {
	warn("can't create a file - assuming filesystem is full\n");
	}
	if (-e $n && unlink($n) != 1) {
	warn("couldn't delete \"$n\"");
	}
	last;
	}
	$_ = `sum -r $n`;
	($sum) = split(/ +/);
	$name = "$n.$sum.data";
	$cmd = "mv $n $name"; # perl rename failed earlier than using mv
	$cmd .= " > /dev/null 2>&1" if (! $verbose);
	if (system($cmd) != 0) {
	if ($verbose) {
	warn("can't rename a file - assuming filesystem is full\n");
	}
	if (-e $name && unlink($name) != 1) {
	warn("couldn't delete \"$name\"");
	}
	last;
	}
	if (defined $list) {
	chomp($_ = `pwd`);
	printf LIST ("%s/%s\n", $_, $name);
	}
	$total += $size;
	$files++;

	if (defined $sync_bytes && int($total / $sync_bytes) > $sync_cnt) {
	$sync_cnt++;
	system("sync");
	}
	}
	# note that if d==0 create directories more frequently than files
	elsif (($d == 0 && $r >= 0.5) \|\| ($d > 0 && $r >= 2.4 && $r < 2.7)) {
	# create a new directory and descend
	$name = sprintf("%04d.d", $names[$d]++);
	if (! mkdir($name, 0777)) {
	warn("can't make a directory - assuming filesystem is full\n");
	last;
	}
	chdir($name) or die();
	$d++;
	$dirs++;
	}
	elsif ($r >= 2.7 && $r < 3.0) {
	# pop up to the parent directory same probability as descend
	die("Error: $progname: panic: shouldn't be here!") if ($d == 0);
	chdir("..") or die();
	$d--;
	}
	}
	# make sure we return to the original working directory
	chdir($cwd) or die();
	$verbose && print STDERR "done\n";
	$verbose && print STDERR "$total bytes (in $files files and $dirs directories) were actually written\n";
	close LIST;
	exit(0) if ($total = $bytes);
	exit(1) if ($total == 0);
	exit(2) if ($total > 0 && $total < $bytes);

	# - to sum all generated data:
	# find /home/fill/ -name \*data \| xargs ls -al \| awk '{total = total + $5; } END { printf("total = %d bytes\n", total); }'
	# - to find any files not of the required size
	# find . -name \*data -a \! -size 4096c
	# - count new files
	# find ./fill -name \*.data \| wc
	# - count new directories
	# find ./fill -name \*.d \| wc