~percona-toolkit-dev/percona-toolkit/pt-stalk-iter-1-bug-1070434

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#!/usr/bin/env bash

# This program is part of Percona Toolkit: http://www.percona.com/software/
# See "COPYRIGHT, LICENSE, AND WARRANTY" at the end of this file for legal
# notices and disclaimers.

usage() {
   if [ "${OPT_ERR}" ]; then
      echo "Error: $OPT_ERR" >&2
   fi
   echo "Usage: pt-sift FILE|PREFIX|DIRECTORY" >&2
   echo "For more information, 'man pt-sift' or 'perldoc $0'." >&2
   exit 1
}

# ###########################################################################
# tmpdir package
# This package is a copy without comments from the original.  The original
# with comments and its test file can be found in the Bazaar repository at,
#   lib/bash/tmpdir.sh
#   t/lib/bash/tmpdir.sh
# See https://launchpad.net/percona-toolkit for more information.
# ###########################################################################


set -u

PT_TMPDIR=""

mk_tmpdir() {
   local dir="${1:-""}"

   if [ -n "$dir" ]; then
      if [ ! -d "$dir" ]; then
         mkdir "$dir" || die "Cannot make tmpdir $dir"
      fi
      PT_TMPDIR="$dir"
   else
      local tool="${0##*/}"
      local pid="$$"
      PT_TMPDIR=`mktemp -d -t "${tool}.${pid}.XXXXXX"` \
         || die "Cannot make secure tmpdir"
   fi
}

rm_tmpdir() {
   if [ -n "$PT_TMPDIR" ] && [ -d "$PT_TMPDIR" ]; then
      rm -rf "$PT_TMPDIR"
   fi
   PT_TMPDIR=""
}

# ###########################################################################
# End tmpdir package
# ###########################################################################

# ###########################################################################
# Global variables
# ###########################################################################

TOOL="pt-sift"
if [ -d "/var/lib/pt-stalk" ]; then
   BASEDIR="/var/lib/pt-stalk"
else
   BASEDIR="$PWD"
fi
PREFIX=""

# ###########################################################################
# Subroutines
# ###########################################################################

sigtrap() {
   echo "Caught signal, exiting" >&2
   rm_tmpdir
   exit 0
}

# Show current help and settings
print_help() {
   cat <<-HELP
   You can control this program with key presses.
                  ---  COMMANDS  ---
      1  Default action: summarize files
      0  Minimal action: list files
      *  View all the files in less
      d  Invoke 'diskstats' on the disk performance data
      i  View the first INNODB STATUS sample in 'less'
      m  Invoke 'pt-mext' to show the SHOW STATUS counters side by side
      n  Summarize the 'netstat -antp' status data
                  --- NAVIGATION ---
      j  Select the next timestamp
      k  Select the previous timestamp
      q  Quit the program
	HELP
}

# ###########################################################################
# Main program loop, called below if tool is ran from the command line.
# ###########################################################################

main() {
   trap sigtrap SIGHUP SIGINT SIGTERM

   # If there's a command-line arg, figure out if it's a file, directory, or
   # prefix.  The outcome of this block of code should be that BASEDIR is the
   # directory where the files live, without a trailing slash; and PREFIX is
   # either empty or a timestamp, such as "2011_02_08_16_58_07".
   if [ $# -gt 1 ]; then
      OPT_ERR="Specify only one PREFIX or DIR"
      usage
   fi

   if [ $# -eq 1 ]; then
      if [ -d "$1" ]; then
         BASEDIR="$1"
         PREFIX=""
      elif [ -f "$1" -o -f "$1-df" -o -f "$1df" ]; then
         BASEDIR="$(dirname "$1")"
         PREFIX="$(echo "$1" | perl -ne '$_ =~ m/([\d_]+)/; print $1;')"
      else
         echo "Error: $1 is not a directory, and there are no pt-stalk files in the curent working directory ($BASEDIR) with a $1 prefix." >&2
         echo "For more information, 'man pt-sift' or 'perldoc $0'." >&2
         exit 1
      fi
   fi

   # If the programs we need don't exist, try to get them.
   # Percona Toolkit tools:
   for prog in pt-diskstats pt-pmp pt-mext pt-align; do
      # A var can't be named "PR_pt-pmp" so we chop of "pt-" to get
      # the program's basename, resulting in "PR_pmp".
      prog_base=${prog#"pt-"}
      if which "$prog" >/dev/null 2>&1 ; then
         eval "PR_$prog_base"="$(which "$prog")"
      elif [ -f "$prog" -a -x "$prog" ]; then
         eval "PR_$prog_base"="./$prog"
      elif [ -f "${BASEDIR}/$prog" -a -x "${BASEDIR}/$prog" ]; then
         eval "PR_$prog_base"="${BASEDIR}/$prog"
      elif which "curl" >/dev/null 2>&1; then
         echo "Fetching $prog" >&2
         curl "http://www.percona.com/get/$prog" > "$prog" && chmod +x "$prog"
         eval "PR_$prog_base"="./$prog"
      else
         echo "Cannot find or fetch required program: $prog" >&2
         exit 1
      fi 
   done

   # Make a secure tmpdir.
   mk_tmpdir

   # We need to generate a list of timestamps, and ask the user to choose one if
   # there is no PREFIX yet.  NOTE: we rely on the "-df" files here.
   (
      cd "$BASEDIR"
      ls *-df 2>/dev/null | cut -d- -f1 | sort > "$PT_TMPDIR/pt-sift.prefixes" 
   )
   if [ ! -s "$PT_TMPDIR/pt-sift.prefixes" ]; then
      echo "Error: There are no pt-stalk files in $BASEDIR" >&2
      echo "For more information, 'man pt-sift' or 'perldoc $0'." >&2
      exit 1
   fi
   if [ -z "${PREFIX}" ]; then
      if [ "$(grep -c . $PT_TMPDIR/pt-sift.prefixes)" = "1" ]; then
         # If there is only one sample, we use it as the prefix.
         PREFIX="$(cat $PT_TMPDIR/pt-sift.prefixes)"
      fi
   fi
   if [ -z "${PREFIX}" ]; then
      echo
      i=0
      cat $PT_TMPDIR/pt-sift.prefixes | while read line; do
         i=$(($i + 1))
         echo -n "  $line"
         if [ $i -eq 3 ]; then
            echo
            i=0
         fi
      done
      # We might have ended mid-line or we might have printed a newline; print a
      # newline if required to end the list of timestamp prefixes.
      awk 'BEGIN { i = 0 } { i++ } END { if ( i % 3 != 0 ) { print "" } }' $PT_TMPDIR/pt-sift.prefixes
      echo
      while [ -z "${PREFIX}" -o "$(grep -c "${PREFIX}" $PT_TMPDIR/pt-sift.prefixes)" -ne 1 ]; do
         DEFAULT="$(tail -1 $PT_TMPDIR/pt-sift.prefixes)"
         read -e -p "Select a timestamp from the list [${DEFAULT}] " ARG
         ARG="${ARG:-${DEFAULT}}"
         if [ "$(grep -c "${ARG}" $PT_TMPDIR/pt-sift.prefixes)" -eq 1 ]; then
            PREFIX="$(grep "${ARG}" $PT_TMPDIR/pt-sift.prefixes)"
         fi
      done
   fi

   KEY=""
   ACTION="DEFAULT"
   while [ "${KEY}" != "q" ]; do

      if [ "${ACTION}" != "INVALID" ]; then
         # Print the current host, timestamp and action.  Figure out if we're at
         # the first or last sample, to make it easy to navigate.
         PAGE="$(awk "/./{i++} /${PREFIX}/{c=i} END{print c, \"of\", i}" $PT_TMPDIR/pt-sift.prefixes)"
         HOST="$(cat "${BASEDIR}/${PREFIX}-hostname" 2>/dev/null)"
         echo -e "======== ${HOST:-unknown} at \033[34m${PREFIX} \033[31m${ACTION}\033[0m (${PAGE}) ========"
      fi

      # Take an action based on the current $ACTION
      case "${ACTION}" in

         # Format a brief report: busiest device's disk stats, CPU stats
         DEFAULT)
            echo "--diskstats--"
            if [ -f "${BASEDIR}/${PREFIX}-diskstats" ]; then

               $PR_diskstats --group-by disk "${BASEDIR}/${PREFIX}-diskstats" \
                  | awk '
                     /ts/ { header = $0 }
                     /[0-9]/ {
                        io  = $3 + $9;
                        if ( io >= mio ) {
                           mio   = io;
                           mseen = $0;
                        }
                     }
                     END {
                        print header;
                        print mseen;
                     }'

               # Find out which device was the busiest.
               mdev="$($PR_diskstats --group-by disk "${BASEDIR}/${PREFIX}-diskstats" \
                  | awk '
                     /[0-9]/ {
                        io  = $3 + $9;
                        if ( io >= mio ) {
                           mio   = io;
                           mdev  = $2;
                        }
                     }
                     END {
                        print mdev;
                     }')"

               # Print the busy% for that device, rounded to the nearest N%, with
               # "." as a marker for a repeated value.
               $PR_diskstats --group-by sample "${BASEDIR}/${PREFIX}-diskstats" \
                  | awk "
                     BEGIN {
                        fuzz = 5;
                        printf \" ${mdev} \"
                     }
                     \$1 = \"${mdev}\" {
                        busy_rounded = fuzz * sprintf(\"%d\", substr(\$15, 1, length(\$15) - 1) / fuzz);
                        if ( printed == 1 && prev == busy_rounded ) {
                           printf \" .\";
                        }
                        else {
                           printf \" %d%%\", busy_rounded;
                           prev    = busy_rounded;
                           printed = 1;
                        }
                     }"
               echo
            else
               echo "    No diskstats file exists"
            fi

            echo "--vmstat--"
            if [ -f "${BASEDIR}/${PREFIX}-vmstat" ]; then
               tail -n 3 "${BASEDIR}/${PREFIX}-vmstat-overall" | $PR_align

               # Figure out which column is 'wa' and print this, similar to the
               # busy% for disks above.
               wa_col="$(awk '/swpd/{for(i=1;i<=NF;++i){if($i=="wa"){print i; exit}}}' "${BASEDIR}/${PREFIX}-vmstat")"
               awk "
                  BEGIN {
                     fuzz = 5;
                     printf \"wa\"
                  }
                  /[0-9]/ {
                     wa_rounded = fuzz * sprintf(\"%d\", \$${wa_col} / fuzz);
                     if ( printed == 1 && prev == wa_rounded ) {
                        printf \" .\";
                     }
                     else {
                        printf \" %d%%\", wa_rounded;
                        prev    = wa_rounded;
                        printed = 1;
                     }
                  }" "${BASEDIR}/${PREFIX}-vmstat"
               echo
            else
               echo "    No vmstat file exists"
            fi

            echo "--innodb--"
            awk '
               /queries inside/ {
                  inside = $0;
               }
               /Main thread/ {
                  main_state = substr($0, index($0, ":") + 2);
               }
               /Pending normal/ {
                  pending_reads += substr($5, 1, length($5) - 1);
                  pending_reads += substr($NF, 1, length($NF) - 1);
               }
               /ibuf aio reads/ {
                  pending_reads += substr($4, 1, length($4) - 1);
                  pending_reads += substr($7, 1, length($7) - 1);
                  pending_reads += $NF;
               }
               /Pending flushes/ {
                  pending_flushes = substr($5, 1, length($5) - 1) + $NF;
               }
               /pending preads/ {
                  pending_reads += $1;
                  pending_writes += $4;
               }
               /pending log writes/ {
                  pending_writes += $1 + $5;
               }
               /Pending reads/ {
                  pending_reads += $NF;
               }
               /Pending writes/ {
                  pending_writes += substr($4, 1, length($4) - 1);
                  pending_writes += substr($7, 1, length($7) - 1);
                  pending_writes += $NF;
               }
               /Log sequence number/ {
                  if ( $NF == 5 ) {
                     lsn = ($4 * (2^32)) + $5;
                  }
                  else {
                     lsn = $4;
                  }
               }
               /Last checkpoint at/ {
                  if ( $NF == 5 ) {
                     chkp = ($4 * (2^32)) + $5;
                  }
                  else {
                     chkp = $4;
                  }
               }
               /END OF INNODB/ {
                  complete = 1;
               }
               /^TRANSACTIONS$/ {
                  tseen = 1;
               }
               /^---TRANSACTION/ {
                  if ( tseen == 1 ) {
                     if ( $2 ~ /,/ ) {
                        status = $3;
                        time   = $4;
                     }
                     else {
                        status = $4;
                        time   = $5;
                     }
                     txns[status]++;
                     if ( time > txntime[status] ) {
                        txntime[status] = time;
                     }
                  }
               }
               /LOCK WAIT/ {
                  if ( tseen == 1 ) {
                     txns["LOCK WAIT"]++;
                     if ( $3 > txntime["LOCK WAIT"] ) {
                        txntime["LOCK WAIT"] = $3;
                     }
                  }
               }
               END {
                  if ( complete != 1 ) {
                     print "    (innodb status is incomplete)";
                  }
                  printf "    txns:";
                  for ( i in txns ) {
                     printf " %dx%s (%ds)", txns[i], i, txntime[i];
                  }
                  print "";
                  if ( inside ) {
                     print "    " inside;
                  }
                  printf "    Main thread: %s, pending reads %d, writes %d, flush %d\n", main_state, pending_reads, pending_writes, pending_flushes;
                  printf "    Log: lsn = %d, chkp = %d, chkp age = %d\n", lsn, chkp, lsn - chkp;
               }
            ' "${BASEDIR}/${PREFIX}-innodbstatus1"
            echo "    Threads are waiting at:"
            awk '/has waited at/ { print $6, $7, $8 }' \
              "${BASEDIR}/${PREFIX}-innodbstatus1" | sort | uniq -c | sort -rn
            echo "    Threads are waiting on:"
            awk '/^[XS]-lock on.*latch/ { print }' \
              "${BASEDIR}/${PREFIX}-innodbstatus1" | sort | uniq -c | sort -rn

            # This section checks for processlist or processlist1 for backwards
            # compatibility with the obsolete pt-collect tool.
            echo "--processlist--"
            local PROCESSLIST_FILE="${BASEDIR}/${PREFIX}-processlist"
            if [ -e "${BASEDIR}/${PREFIX}-processlist1" ]; then
               PROCESSLIST_FILE="${BASEDIR}/${PREFIX}-processlist1"
            fi
            for word in State Command; do
               echo "    $word"
               awk -F: -v column="$word" '
               BEGIN {
                  regex = "^ *" column
               }
               {
                  if ( $1 ~ regex ) {
                     print $2;
                  }
                  # Newer versions of pt-stalk gather several samples. We will
                  # analyze only the first sample.
                  if ( $0 ~ /^TS/ ) {
                     ts++;
                     if (ts > 1) {
                        exit
                     }
                  }
               }' "${PROCESSLIST_FILE}" \
                  | sort | uniq -c | sort -rn | head -n 5
            done

            echo "--stack traces--"
            if [ -e "${BASEDIR}/${PREFIX}-stacktrace" ]; then
               $PR_pmp -l 5 "${BASEDIR}/${PREFIX}-stacktrace" | head -n 5
            else
               echo "    No stack trace file exists"
            fi

            echo "--oprofile--"
            if [ ! -e "${BASEDIR}/${PREFIX}-opreport" ]; then
               echo "    No opreport file exists"
            fi
            test -e "${BASEDIR}/${PREFIX}-opreport" && awk '
               {
                  if ( $1 == "samples" ) {
                     go = 1;
                  }
                  if ( go == 1 ) {
                     print "    " $0;
                     if ( printed++ == 6 ) {
                        exit;
                     }
                  }
               } ' "${BASEDIR}/${PREFIX}-opreport"
            ;;

         LIST)
            ls -lh ${BASEDIR}/${PREFIX}-*
            ;;

         VIEW)
            echo "Viewing all files"
            less -i ${BASEDIR}/${PREFIX}-*
            echo "Press a key to continue or choose a different action"
            ;;

         DISKSTATS)
            echo "Starting $PR_diskstats"
            $PR_diskstats "${BASEDIR}/${PREFIX}-diskstats"
            echo "Press a key to continue or choose a different action"
            ;;

         INNODB)
            echo "Viewing InnoDB files"
            less -i "${BASEDIR}/${PREFIX}-innodbstatus1"
            echo "Press a key to continue or choose a different action"
            ;;

         MEXT)
            echo "Displaying the first 4 samples of SHOW STATUS counters"
            # Grab the first 4 samples by looking for blank lines.
            # I'll rewrite pt-mext and this will be simpler in future.
            # TODO: upgrade, if pt-mext is fixed :)
            awk '/---/{if(i++>12){exit}}{print}' "${BASEDIR}/${PREFIX}-mysqladmin" | $PR_mext -r -- cat - | less -S
            echo "Press a key to continue or choose a different action"
            ;;

         NETWORK)
            echo "Source of connections to port 3306"
            awk '
               /:3306/ {
                  print substr($5, 0, index($5, ":") - 1);
               }
               /TS/ {
                  if ( i++ > 1 ) {
                     # Stop after the first sample
                     exit;
                  }
               }' "${BASEDIR}/${PREFIX}-netstat" | sort | uniq -c | sort -rn
            echo "Status of connections to port 3306"
            awk '
               /:3306/ {
                  print $6;
               }
               /TS/ {
                  if ( i++ > 1 ) {
                     # Stop after the first sample
                     exit;
                  }
               }' "${BASEDIR}/${PREFIX}-netstat" | sort | uniq -c | sort -rn
            echo "Press a key to continue or choose a different action"
            ;;

         INVALID)
            ;;

      esac

      # Capture and handle the interactive key-strokes.
      tput sgr0
      KEY=""
      if ! read -n 1 -s KEY 2>/dev/null; then
         echo "Error while trying to read interactive keystroke command. Exiting."
         exit
      fi
      case "${KEY:-}" in
         j|k)
            PREFIX="$(awk "
               BEGIN {
                  printed = 0;
               }
               {
                  prev=curr;
                  curr=\$1;
                  if ( \"j\" == \"${KEY}\" && prev == \"${PREFIX}\" && curr ~ /./ ) {
                     print curr;
                     printed = 1;
                     exit;
                  }
                  if ( \"k\" == \"${KEY}\" && curr == \"${PREFIX}\" && prev ~ /./ ) {
                     print prev;
                     printed = 1;
                     exit;
                  }
               }
               END {
                  if ( printed == 0 ) {
                     print \"${PREFIX}\";
                  }
               }" $PT_TMPDIR/pt-sift.prefixes)"
            ;;
         1)
            ACTION="DEFAULT"
            ;;
         0)
            ACTION="LIST"
            ;;
         '*')
            ACTION="VIEW"
            ;;
         d)
            ACTION="DISKSTATS"
            ;;
         i)
            ACTION="INNODB"
            ;;
         m)
            ACTION="MEXT"
            ;;
         n)
            ACTION="NETWORK"
            ;;
         q)
            ;;
         '?')
            print_help
            echo "Press any key to continue"
            read -n 1 -s
            ;;
         *)
            echo "Unknown key '${KEY}'; press ? for help"
            ACTION="INVALID"
            ;;
      esac
   done

   rm_tmpdir
}

# Execute the program if it was not included from another file.  This makes it
# possible to include without executing, and thus test.
if    [ "${0##*/}" = "$TOOL" ] \
   || [ "${0##*/}" = "bash" -a "$_" = "$0" ]; then
    main "${@:-""}"
fi

# ############################################################################
# Documentation
# ############################################################################
:<<'DOCUMENTATION'
=pod

=head1 NAME

pt-sift - Browses files created by pt-stalk.

=head1 SYNOPSIS

Usage: pt-sift FILE|PREFIX|DIRECTORY

pt-sift browses files created by L<pt-stalk>.  If no options are given,
the tool browses all pt-stalk files in C</var/lib/pt-stalk> if that directory
exists, else the current working directory is used.  If a FILE is given,
the tool browses files with the same prefix in the given file's directory.
If a PREFIX is given, the tool browses files in C</var/lib/pt-stalk>
(or the current working directory) with the same prefix.  If a DIRECTORY
is given, the tool browses all pt-stalk files in it.

=head1 RISKS

The following section is included to inform users about the potential risks,
whether known or unknown, of using this tool.  The two main categories of risks
are those created by the nature of the tool (e.g. read-only tools vs. read-write
tools) and those created by bugs.

pt-sift is a read-only tool.  It should be very low-risk.

At the time of this release, we know of no bugs that could cause serious harm
to users.

The authoritative source for updated information is always the online issue
tracking system.  Issues that affect this tool will be marked as such.  You can
see a list of such issues at the following URL:
L<http://www.percona.com/bugs/pt-sift>.

See also L<"BUGS"> for more information on filing bugs and getting help.

=head1 DESCRIPTION

pt-sift downloads other tools that it might need, such as L<pt-diskstats>,
and then makes a list of the unique timestamp prefixes of all the files in
the directory, as written by the L<pt-stalk> tool.  If the user specified
a timestamp on the command line, then it begins with that sample of data;
otherwise it begins by showing a list of the timestamps and prompting for
a selection.  Thereafter, it displays a summary of the selected sample, and
the user can navigate and inspect with keystrokes.  The keystroke commands
you can use are as follows:

=over

=item d

Sets the action to start the L<pt-diskstats> tool on the sample's disk
performance statistics.

=item i

Sets the action to view the first INNODB STATUS sample in less.

=item m

Displays the first 4 samples of SHOW STATUS counters side by side with the
L<pt-mext> tool.

=item n

Summarizes the first sample of netstat data in two ways: by originating host,
and by connection state.

=item j

Select the next timestamp as the active sample.

=item k

Select the previous timestamp as the active sample.

=item q

Quit the program.

=item 1

Sets the action for each sample to the default, which is to view a summary
of the sample.

=item 0

Sets the action to just list the files in the sample.

=item *

Sets the action to view all of the sample's files in the less program.

=back

=head1 OPTIONS

This tool does not have any command-line options.

=head1 ENVIRONMENT

This tool does not use any environment variables.

=head1 SYSTEM REQUIREMENTS

This tool requires Bash v3 and the following programs: pt-diskstats, pt-pmp,
pt-mext, and pt-align.  If these programs are not in your PATH,
they will be fetched from the Internet if curl is available.

=head1 BUGS

For a list of known bugs, see L<http://www.percona.com/bugs/pt-sift>.

Please report bugs at L<https://bugs.launchpad.net/percona-toolkit>.
Include the following information in your bug report:

=over

=item * Complete command-line used to run the tool

=item * Tool L<"--version">

=item * MySQL version of all servers involved

=item * Output from the tool including STDERR

=item * Input files (log/dump/config files, etc.)

=back

If possible, include debugging output by running the tool with C<PTDEBUG>;
see L<"ENVIRONMENT">.

=head1 DOWNLOADING

Visit L<http://www.percona.com/software/percona-toolkit/> to download the
latest release of Percona Toolkit.  Or, get the latest release from the
command line:

   wget percona.com/get/percona-toolkit.tar.gz

   wget percona.com/get/percona-toolkit.rpm

   wget percona.com/get/percona-toolkit.deb

You can also get individual tools from the latest release:

   wget percona.com/get/TOOL

Replace C<TOOL> with the name of any tool.

=head1 AUTHORS

Baron Schwartz

=head1 ABOUT PERCONA TOOLKIT

This tool is part of Percona Toolkit, a collection of advanced command-line
tools developed by Percona for MySQL support and consulting.  Percona Toolkit
was forked from two projects in June, 2011: Maatkit and Aspersa.  Those
projects were created by Baron Schwartz and developed primarily by him and
Daniel Nichter, both of whom are employed by Percona.  Visit
L<http://www.percona.com/software/> for more software developed by Percona.

=head1 COPYRIGHT, LICENSE, AND WARRANTY

This program is copyright 2010-2011 Baron Schwartz, 2011-2012 Percona Inc.
Feedback and improvements are welcome.

THIS PROGRAM IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation, version 2; OR the Perl Artistic License.  On UNIX and similar
systems, you can issue `man perlgpl' or `man perlartistic' to read these
licenses.

You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place, Suite 330, Boston, MA  02111-1307  USA.

=head1 VERSION

pt-sift 2.1.5

=cut

DOCUMENTATION