Merge lp:~percona-toolkit-dev/percona-toolkit/partial-fix-1063912-ptc-pxc-slaves into lp:~percona-toolkit-dev/percona-toolkit/2.1.5-release

[Daniel Nichter]

[lp:~percona-toolkit-dev/percona-toolkit/partial-fix-1063912-ptc-pxc-slaves]

405. By Daniel Nichter on 2012-10-08

Add note to PXC limiations that complex repl setups aren't supported.

[Daniel Nichter (daniel-nichter)]

review: Approve

=== modified file 'bin/pt-query-digest'
--- bin/pt-query-digest	2012-09-24 19:24:36 +0000
+++ bin/pt-query-digest	2012-10-08 18:50:28 +0000
@@ -15160,8 +15160,10 @@
 may actually include different kinds of attributes (for example, you may have a
 server with the Percona patches).
 
-For a full list of attributes, see
-L<http://code.google.com/p/maatkit/wiki/EventAttributes>.
+See L<"ATTRIBUTES REFERENCE"> near the end of this documentation for a list
+of common and L<"--type"> specific attributes.  A familiarity with these
+attributes is necessary for working with L<"--filter">,
+L<"--ignore-attributes">, and other attribute-related options.
 
 With creative use of L<"--filter">, you can create new attributes derived
 from existing attributes.  For example, to create an attribute called
@@ -15189,8 +15191,8 @@
 These attributes are no different from slow log attributes, so you can use them
 with L<"--[no]report">, L<"--group-by">, in a L<"--filter">, etc.
 
-These attributes and more are documented at
-L<http://code.google.com/p/maatkit/wiki/EventAttributes>.
+See the memcached section of L<"ATTRIBUTES REFERENCE"> for a list of
+memcached-specific attributes.
 
 =head1 OUTPUT
 
@@ -15835,8 +15837,8 @@
 
 It is permissible for the code to have side effects (to alter C<$event>).
 
-You can find an explanation of the structure of $event at
-L<http://code.google.com/p/maatkit/wiki/EventAttributes>.
+See L<"ATTRIBUTES REFERENCE"> for a list of common and L<"--type"> specific
+attributes.
 
 Here are more examples of filter code:
 
@@ -17069,6 +17071,206 @@
 
 Replace C<TOOL> with the name of any tool.
 
+=head1 ATTRIBUTES REFERENCE
+
+Events may have the following attributes.  If writing a L<"--filter">,
+be sure to check that an attribute is defined in each event before
+using it, else the filter code may crash the tool with a
+"use of uninitialized value" error.
+
+You can dump event attributes for any input like:
+
+  $ pt-query-digest \
+      slowlog \
+      --filter 'print Dumper $event' \
+      --no-report \
+      --sample 1
+
+That will produce a lot of output with "attribute => value" pairs like:
+
+   $VAR1 = {
+     Query_time => '0.033384',
+     Rows_examined => '0',
+     Rows_sent => '0',
+     Thread_id => '10',
+     Tmp_table => 'No',
+     Tmp_table_on_disk => 'No',
+     arg => 'SELECT col FROM tbl WHERE id=5',
+     bytes => 103,
+     cmd => 'Query',
+     db => 'db1',
+     fingerprint => 'select col from tbl where id=?',
+     host => '',
+     pos_in_log => 1334,
+     ts => '071218 11:48:27',
+     user => '[SQL_SLAVE]'
+   };
+
+=head2 COMMON
+
+These attribute are common to all input L<"--type"> and L<"--processlist">,
+except where noted.
+
+=over
+
+=item arg
+
+The query text, or the command for admin commands like C<Ping>.
+
+=item bytes
+
+The byte length of the C<arg>.
+
+=item cmd
+
+"Query" or "Admin" for all except memcached. For memcached it's
+the memcached command: get, set, etc.
+
+=item db
+
+The current database, except for memcached.  The value comes from USE
+database statements.  By default, C<Schema> is an alias which is automatically
+changed to C<db>; see L<"--attribute-aliases">.
+
+=item fingerprint 
+
+An abstracted form of the query.  See L<"FINGERPRINTS">.
+
+=item host
+
+Client host which executed the query.
+
+=item pos_in_log
+
+The byte offset of the event in the log or tcpdump,
+except for L<"--processlist">.
+
+=item Query_time
+
+The total time the query took, including lock time.
+
+=item ts
+
+The timestamp of when the query ended.
+
+=back
+
+=head2 SLOW, GENERAL, AND BINARY LOGS
+
+Events have all available attributes from the log file.  Therefore, you only
+need to look at the log file to see which events are available, but remember:
+not all events have the same attributes.
+
+Percona Server adds many attributes to the slow log; see
+http://www.percona.com/doc/percona-server/5.1/diagnostics/slow_extended.html#changes-to-the-log-format
+for more information.
+
+=head2 TCPDUMP
+
+These attributes are available when parsing L<"--type"> tcpdump.
+
+=over
+
+=item Error_no
+
+The MySQL error number if the query caused an error.
+
+=item ip
+
+The client's IP address.  Certain log files may also contain this attribute.
+
+=item No_good_index_used
+
+Yes or No if no good index existed for the query (flag set by server).
+
+=item No_index_used
+
+Yes or No if the query did not use any index (flag set by server).
+
+=item port
+
+The client's port number.
+
+=item Warning_count
+
+The number of warnings, as otherwise shown by C<SHOW WARNINGS>.
+
+=back
+
+=head2 PROCESSLIST
+
+If using L<"--processlist">, an C<id> attribute is available for
+the process ID, in addition to the common attributes.
+
+=head2 MEMCACHED
+
+These attributes are available when parsing L<"--type"> memcached.
+
+=over
+
+=item exptime
+
+Expiration time.
+
+=item key
+
+The key used by cmd.
+
+=item key_print
+
+An abstracted form of the key.
+
+=item Memc_add
+
+Yes/No if the command is add.
+
+=item Memc_append
+
+Yes/No if the command is append.
+
+=item Memc_cas
+
+Yes/No if the command is cas.
+
+=item Memc_error
+
+Yes/No if command caused an error. Currently, the only error is when
+a retrieval command is interrupted.
+
+=item Memc_get
+
+Yes/No if the command is get.
+
+=item Memc_gets
+
+Yes/No if the command is gets.
+
+=item Memc_miss
+
+Yes/No if the command tried to access a nonexistent key.
+
+=item Memc_prepend
+
+Yes/No if the command is prepend.
+
+=item Memc_replace
+
+Yes/No if the command is replace.
+
+=item Memc_set
+
+Yes/No if the command is set.
+
+=item res
+
+Result of cmd.
+
+=item val
+
+The return value of cmd, if any.
+
+=back
+
 =head1 AUTHORS
 
 Baron Schwartz and Daniel Nichter
 
=== modified file 'bin/pt-stalk'
--- bin/pt-stalk	2012-09-20 13:59:16 +0000
+++ bin/pt-stalk	2012-10-08 18:50:28 +0000
@@ -933,6 +933,30 @@
 ITER=1
 
 # ###########################################################################
+# Plugin hooks
+# ###########################################################################
+
+before_stalk() {
+   :
+}
+
+before_collect() {
+   :
+}
+
+after_collect() {
+   :
+}
+
+after_collect_sleep() {
+   :
+}
+
+after_stalk() {
+   :
+}
+
+# ###########################################################################
 # Subroutines
 # ###########################################################################
 
@@ -1016,12 +1040,12 @@
 
 oktorun() {
    if [ $OKTORUN -eq 0 ]; then
-      EXIT_REASON="OKTORUN is false"
+      [ -z "$EXIT_REASON" ] && EXIT_REASON="OKTORUN is false"
       return 1  # stop running
    fi
 
    if [ -n "$OPT_ITERATIONS" ] && [ $ITER -gt $OPT_ITERATIONS ]; then
-      EXIT_REASON="no more iterations"
+      [ -z "$EXIT_REASON" ] && EXIT_REASON="no more iterations"
       return 1  # stop running
    fi
 
@@ -1136,6 +1160,9 @@
                log "pt-stalk ran with $RAN_WITH" >> "$OPT_DEST/$prefix-trigger"
                last_prefix="$prefix"
 
+               # Plugin hook:
+               before_collect
+
                # Fork and background the collect subroutine which will
                # run for --run-time seconds.  We (the parent) sleep
                # while its collecting (hopefully --sleep is longer than
@@ -1143,7 +1170,11 @@
                (
                   collect "$OPT_DEST" "$prefix"
                ) >> "$OPT_DEST/$prefix-output" 2>&1 &
-               log "Collector PID $!"
+               local collector_pid=$!
+               log "Collector PID $collector_pid"
+
+               # Plugin hook:
+               after_collect $collector_pid
             else 
                # There will not be enough disk space, so do not collect.
                warn "Collect canceled because there will not be enough disk space after collecting another $margin MB"
@@ -1156,6 +1187,9 @@
          ITER=$((ITER + 1))
          cycles_true=0
          sleep_ok "$OPT_SLEEP" "Sleeping $OPT_SLEEP seconds after collect"
+
+         # Plugin hook:
+         after_collect_sleep
       else
          # Trigger/check/value is ok, sleep until next check.
          sleep_ok "$OPT_INTERVAL"
@@ -1178,7 +1212,7 @@
    # Note: $$ is the parent's PID, but we're a child proc.
    # Bash 4 has $BASHPID but we can't rely on that.  Consequently,
    # we don't know our own PID.  See the usage of $! below.
-   RAN_WITH="--function=$OPT_FUNCTION --variable=$OPT_VARIABLE --threshold=$OPT_THRESHOLD --match=$OPT_MATCH --cycles=$OPT_CYCLES --interval=$OPT_INTERVAL --iterations=$OPT_ITERATIONS --run-time=$OPT_RUN_TIME --sleep=$OPT_SLEEP --dest=$OPT_DEST --prefix=$OPT_PREFIX --notify-by-email=$OPT_NOTIFY_BY_EMAIL --log=$OPT_LOG --pid=$OPT_PID"
+   RAN_WITH="--function=$OPT_FUNCTION --variable=$OPT_VARIABLE --threshold=$OPT_THRESHOLD --match=$OPT_MATCH --cycles=$OPT_CYCLES --interval=$OPT_INTERVAL --iterations=$OPT_ITERATIONS --run-time=$OPT_RUN_TIME --sleep=$OPT_SLEEP --dest=$OPT_DEST --prefix=$OPT_PREFIX --notify-by-email=$OPT_NOTIFY_BY_EMAIL --log=$OPT_LOG --pid=$OPT_PID --plugin=$OPT_PLUGIN"
 
    log "Starting $0 $RAN_WITH"
 
@@ -1190,9 +1224,15 @@
    # Make a secure tmpdir.
    mk_tmpdir
 
+   # Plugin hook:
+   before_stalk
+
    # Stalk while oktorun.
    stalk
 
+   # Plugin hook:
+   after_stalk
+
    # Clean up.
    rm_tmpdir
    remove_pid_file "$OPT_PID"
@@ -1217,6 +1257,15 @@
       option_error "Invalid --function value: $OPT_FUNCTION"
    fi
 
+   # Verify and source the --plugin.
+   if [ "$OPT_PLUGIN" ]; then
+      if [ -f "$OPT_PLUGIN" ]; then
+         . "$OPT_PLUGIN"
+      else
+         option_error "Invalid --plugin value: $OPT_PLUGIN is not a file"
+      fi
+   fi
+
    if [ -z "$OPT_STALK" -a "$OPT_COLLECT" ]; then
       # Not stalking; do immediate collect once.
       OPT_ITERATIONS=1
@@ -1611,6 +1660,66 @@
 
 Create a PID file when daemonized.
 
+=item --plugin
+
+type: string
+
+Load a plugin to hook into the tool and extend is functionality.
+The specified file does not need to be executable, nor does its first line
+need to be shebang line.  It only needs to define one or more of these
+Bash functions:
+
+=over
+
+=item before_stalk
+
+Called before stalking.
+
+=item before_collect
+
+Called when the stalk condition is triggered, before running a collector
+process as a backgrounded subshell.
+
+=item after_collect
+
+Called after running a collector process.  The PID of the collector process
+is passed as the first argument.  This hook is called before
+C<after_collect_sleep>.
+
+=item after_collect_sleep
+
+Called after sleeping L<"--sleep"> seconds for the collector process to finish.
+This hook is called after C<after_collect>.
+
+=item after_stalk
+
+Called after stalking.  Since pt-stalk stalks forever by default,
+this hook is only called if L<"--iterations"> is specified.
+
+=back
+
+For example, a very simple plugin that touches a file when a collector
+process is triggered:
+
+   before_colllect() {
+      touch /tmp/foo
+   }
+
+Since the plugin is completely sourced (imported) into the tool's namespace,
+be careful not to define other functions or global variables that already
+exist in the tool.  You should prefix all plugin-specific functions and
+global variables with C<plugin_> or C<PLUGIN_>.
+
+Plugins have access to all command line options but they should not modify
+them.  Each option is a global variable like C<$OPT_DEST> which corresponds
+to L<"--dest">.  Therefore, the global variable for each command line option
+is C<OPT_> plus the option name in all caps with hyphens replaced by
+underscores.
+
+Plugins can stop the tool by setting the global variable C<OKTORUN>
+to C<1>.  In this case, the global variable C<EXIT_REASON> should also
+be set to indicate why the tool was stopped.
+
 =item --prefix 
 
 type: string
 
=== modified file 'bin/pt-table-checksum'
--- bin/pt-table-checksum	2012-10-05 22:28:45 +0000
+++ bin/pt-table-checksum	2012-10-08 18:50:28 +0000
@@ -3320,7 +3320,9 @@
    PTDEBUG && _d($sql);
    my $row = $self->{dbh}->selectrow_arrayref($sql);
    PTDEBUG && _d(defined $row ? @$row : 'undef');
-   $self->{is_cluster_node} = $row && $row->[0] ? 1 : 0;
+   $self->{is_cluster_node} = $row && $row->[1]
+                            ? ($row->[1] eq 'ON' || $row->[1] eq '1')
+                            : 0;
   
    return $self->{is_cluster_node};
 }
@@ -5146,6 +5148,9 @@
    my $func       = $args{func} || uc($o->get('function'));
    my $cols       = $self->get_checksum_columns(%args);
 
+   die "all columns are excluded by --columns or --ignore-columns"
+      unless @{$cols->{select}};
+      
    my $query;
    if ( !$args{no_cols} ) {
       $query = join(', ',
@@ -9340,11 +9345,20 @@
          # Make a nibble iterator for this table.  This should only fail
          # if the table has no indexes and is too large to checksum in
          # one chunk.
-         my $checksum_cols = $rc->make_chunk_checksum(
-            dbh => $master_cxn->dbh(),
-            tbl => $tbl,
-            %crc_args
-         );
+         my $checksum_cols = eval {
+            $rc->make_chunk_checksum(
+               dbh => $master_cxn->dbh(),
+               tbl => $tbl,
+               %crc_args
+            );
+         };
+
+         if ( $EVAL_ERROR ) {
+            warn ts("Skipping table $tbl->{db}.$tbl->{tbl} because "
+                  . "$EVAL_ERROR\n");
+            return;
+         }
+
          my $nibble_iter;
          eval {
             $nibble_iter = new OobNibbleIterator(
@@ -10664,7 +10678,8 @@
 
 short form: -c; type: array; group: Filter
 
-Checksum only this comma-separated list of columns.
+Checksum only this comma-separated list of columns. If a table doesn't have
+any of the specified columns it will be skipped.
 
 =item --config
 
@@ -10780,6 +10795,8 @@
 type: Hash; group: Filter
 
 Ignore this comma-separated list of columns when calculating the checksum.
+If a table has all of its columns filtered by --ignore-columns, it will
+be skipped.
 
 =item --ignore-databases
 
@@ -11313,6 +11330,12 @@
 cannot be detected automatically.  The lag check (see L<"REPLICA CHECKS">)
 is not performed for cluster nodes.
 
+Mixed replication setups are not currently supported.  For example, the tool
+does not work completely if the master host is replicating to a cluster,
+or if the cluster is replicating to another cluster.  In short, the only
+supported setup is a single cluster with nodes optionally having traditional
+replication slaves.
+
 =back
 
 =head1 BUGS
 
=== modified file 'lib/Cxn.pm'
--- lib/Cxn.pm	2012-08-29 22:35:17 +0000
+++ lib/Cxn.pm	2012-10-08 18:50:28 +0000
@@ -203,7 +203,9 @@
    PTDEBUG && _d($sql);
    my $row = $self->{dbh}->selectrow_arrayref($sql);
    PTDEBUG && _d(defined $row ? @$row : 'undef');
-   $self->{is_cluster_node} = $row && $row->[0] ? 1 : 0;
+   $self->{is_cluster_node} = $row && $row->[1]
+                            ? ($row->[1] eq 'ON' || $row->[1] eq '1')
+                            : 0;
   
    return $self->{is_cluster_node};
 }
 
=== modified file 'lib/RowChecksum.pm'
--- lib/RowChecksum.pm	2012-06-07 03:36:07 +0000
+++ lib/RowChecksum.pm	2012-10-08 18:50:28 +0000
@@ -67,6 +67,11 @@
    my $func       = $args{func} || uc($o->get('function'));
    my $cols       = $self->get_checksum_columns(%args);
 
+   # Skip tables that have all their columns skipped; See
+   # https://bugs.launchpad.net/percona-toolkit/+bug/1016131
+   die "all columns are excluded by --columns or --ignore-columns"
+      unless @{$cols->{select}};
+      
    # Prepend columns to query, resulting in "col1, col2, FUNC(..col1, col2...)",
    # unless caller says not to.  The only caller that says not to is
    # make_chunk_checksum() which uses this row checksum as part of a larger
 
=== modified file 't/lib/Pingback.t'
--- t/lib/Pingback.t	2012-09-13 13:39:04 +0000
+++ t/lib/Pingback.t	2012-10-08 18:50:28 +0000
@@ -126,9 +126,19 @@
       );
    }
 
+   my $expect_post;
+   if ( $args{post} ) {
+      $expect_post = join("\n",
+         map { "$_->{id};$_->{item};$_->{val}" }
+         sort {
+         $a->{item} cmp $b->{item} ||
+         $a->{id}   cmp $b->{id}
+      } @{$args{post}});
+      $expect_post .= "\n";
+   }
    is(
       $post ? ($post->{content} || '') : '',
-      $args{post},
+      $expect_post || '',
       "$args{name} client response"
    );
 
@@ -152,7 +162,18 @@
       }
    ],
    # client should POST this
-   post => "$general_id;Data::Dumper;$dd_ver\n$general_id;Perl;$perl_ver\n",
+   post => [
+      {
+         item => 'Data::Dumper',
+         id   => $general_id,
+         val  => $dd_ver,
+      },
+      {
+         item => 'Perl',
+         id   => $general_id,
+         val  => $perl_ver,
+      },
+   ],
    # Server should return these suggetions after the client posts
    sug  => [
       'Data::Printer is nicer.',
@@ -174,7 +195,18 @@
         content => "",
       }
    ],
-   post => "$general_id;Data::Dumper;$dd_ver\n$general_id;Perl;$perl_ver\n",
+   post => [
+      {
+         item => 'Data::Dumper',
+         id   => $general_id,
+         val  => $dd_ver,
+      },
+      {
+         item => 'Perl',
+         id   => $general_id,
+         val  => $perl_ver,
+      },
+   ],
    sug  => undef,
 );
 
@@ -184,7 +216,7 @@
    name => "No response to GET",
    response => [],
    no_response => 1,
-   post => "",
+   post => undef,
    sug  => undef,
 );
 
@@ -199,7 +231,18 @@
         content => "Perl;perl_version;PERL_VERSION\nData::Dumper;perl_module_version\n",
       },
    ],
-   post => "$general_id;Data::Dumper;$dd_ver\n$general_id;Perl;$perl_ver\n",
+   post => [
+      {
+         id   => $general_id,
+         item => 'Data::Dumper',
+         val  => $dd_ver,
+      },
+      {
+         id   => $general_id,
+         item => 'Perl',
+         val  => $perl_ver,
+      },
+   ],
    sug  => undef,
 );
 
@@ -223,7 +266,13 @@
          }
       ],
       # client should POST this
-      post => "$master_id;MySQL;$mysql_ver $mysql_distro\n",
+      post => [
+         {
+            id   => $master_id,
+            item => 'MySQL',
+            val  => "$mysql_ver $mysql_distro",
+         }
+      ],
       # Server should return these suggetions after the client posts
       sug => ['Percona Server is fast.'],
    );
@@ -440,7 +489,18 @@
          }
       ],
       # client should POST this
-      post => "$slave1_id;MySQL;$mysql_ver $mysql_distro\n$master_id;MySQL;$mysql_ver $mysql_distro\n",
+      post => [
+         {
+            id   => $slave1_id,
+            item => 'MySQL',
+            val  => "$mysql_ver $mysql_distro",
+         },
+         {
+            id   => $master_id,
+            item => 'MySQL',
+            val  => "$mysql_ver $mysql_distro",
+         }
+      ],
       # Server should return these suggetions after the client posts
       sug => [
          'Percona Server is fast.',
 
=== modified file 't/lib/RowChecksum.t'
--- t/lib/RowChecksum.t	2012-06-03 17:54:32 +0000
+++ t/lib/RowChecksum.t	2012-10-08 18:50:28 +0000
@@ -26,9 +26,6 @@
 if ( !$dbh ) {
    plan skip_all => "Cannot connect to sandbox master";
 }
-else {
-   plan tests => 29;
-}
 
 $sb->create_dbs($dbh, ['test']);
 
@@ -421,9 +418,53 @@
    'Ignores specified columns'
 );
 
+# #############################################################################
+# crash with --columns if none match / --ignore-columns if everything is ignored
+# https://bugs.launchpad.net/percona-toolkit/+bug/1016131
+# #############################################################################
+# Re-using the $tbl from the previous test!
+local @ARGV = ('--ignore-columns', 'a,b,c');
+$o->get_opts();
+local $EVAL_ERROR;
+eval {
+   $c->make_row_checksum(
+      tbl  => $tbl,
+      func => 'CRC32',
+   );
+};
+
+like(
+   $EVAL_ERROR,
+   qr/all columns are excluded by --columns or --ignore-columns/,
+   "Dies if all columns are ignored by --ignore-columns"
+);
+
+
+$tbl = {
+   db         => 'mysql',
+   tbl        => 'user',
+   tbl_struct => $tp->parse($tp->get_create_table($dbh, 'mysql', 'user')),
+};
+local @ARGV = qw(--columns some_column_that_doesnt_exist);
+$o->get_opts();
+local $EVAL_ERROR;
+eval {
+   $c->make_row_checksum(
+      tbl  => $tbl,
+      func => 'SHA1',
+   );
+};
+
+like(
+   $EVAL_ERROR,
+   qr/all columns are excluded by --columns or --ignore-columns/,
+   'Dies if all columns are ignored by --columns'
+);
+
 # ############################################################################
 # Done.
 # ############################################################################
 $sb->wipe_clean($dbh);
 ok($sb->ok(), "Sandbox servers") or BAIL_OUT(__FILE__ . " broke the sandbox");
-exit;
+
+done_testing;
 
=== added file 't/pt-stalk/plugin.t'
--- t/pt-stalk/plugin.t	1970-01-01 00:00:00 +0000
+++ t/pt-stalk/plugin.t	2012-10-08 18:50:28 +0000
@@ -0,0 +1,74 @@
+#!/usr/bin/env perl
+
+BEGIN {
+   die "The PERCONA_TOOLKIT_BRANCH environment variable is not set.\n"
+      unless $ENV{PERCONA_TOOLKIT_BRANCH} && -d $ENV{PERCONA_TOOLKIT_BRANCH};
+   unshift @INC, "$ENV{PERCONA_TOOLKIT_BRANCH}/lib";
+};
+
+use strict;
+use warnings FATAL => 'all';
+use English qw(-no_match_vars);
+use Test::More;
+use Time::HiRes qw(sleep);
+
+use PerconaTest;
+use DSNParser;
+use Sandbox;
+
+my $dp = new DSNParser(opts=>$dsn_opts);
+my $sb = new Sandbox(basedir => '/tmp', DSNParser => $dp);
+my $dbh = $sb->get_dbh_for('master');
+
+if ( !$dbh ) {
+   plan skip_all => 'Cannot connect to sandbox master';
+}
+
+my $cnf      = "/tmp/12345/my.sandbox.cnf";
+my $pid_file = "/tmp/pt-stalk.pid.$PID";
+my $log_file = "/tmp/pt-stalk.log.$PID";
+my $dest     = "/tmp/pt-stalk.collect.$PID";
+my $output;
+my $retval;
+my $pid;
+
+diag(`rm $pid_file 2>/dev/null`);
+diag(`rm $log_file 2>/dev/null`);
+diag(`mkdir $dest`);
+
+# We'll have to watch Uptime since it's the only status var that's going
+# to be predictable.
+my (undef, $uptime) = $dbh->selectrow_array("SHOW STATUS LIKE 'Uptime'");
+my $threshold = $uptime + 2;
+
+$retval = system("$trunk/bin/pt-stalk --iterations 1 --dest $dest --variable Uptime --threshold $threshold --cycles 1 --run-time 2 --pid $pid_file --plugin $trunk/t/pt-stalk/samples/plugin001.sh -- --defaults-file=$cnf >$log_file 2>&1");
+
+PerconaTest::wait_until(sub { !-f $pid_file });
+
+is(
+   $retval >> 8,
+   0,
+   "Exit 0"
+);
+
+foreach my $hook (qw(
+   before_stalk
+   before_collect
+   after_collect
+   after_collect_sleep
+   after_stalk
+)) {
+   ok(
+      -f "$dest/$hook",
+      "$hook hook called"
+   );
+}
+
+# #############################################################################
+# Done.
+# #############################################################################
+diag(`rm $pid_file 2>/dev/null`);
+diag(`rm $log_file 2>/dev/null`);
+diag(`rm -rf $dest 2>/dev/null`);
+ok($sb->ok(), "Sandbox servers") or BAIL_OUT(__FILE__ . " broke the sandbox");
+done_testing;
 
=== added file 't/pt-stalk/samples/plugin001.sh'
--- t/pt-stalk/samples/plugin001.sh	1970-01-01 00:00:00 +0000
+++ t/pt-stalk/samples/plugin001.sh	2012-10-08 18:50:28 +0000
@@ -0,0 +1,21 @@
+#!/bin/sh
+
+before_stalk() {
+   date >> "$OPT_DEST/before_stalk"
+}
+
+before_collect() {
+   date >> "$OPT_DEST/before_collect"
+}
+
+after_collect() {
+   date >> "$OPT_DEST/after_collect"
+}
+
+after_collect_sleep() {
+   date >> "$OPT_DEST/after_collect_sleep"
+}
+
+after_stalk() {
+   date >> "$OPT_DEST/after_stalk"
+}
 
=== modified file 't/pt-table-checksum/bugs.t'
--- t/pt-table-checksum/bugs.t	2012-07-27 17:52:24 +0000
+++ t/pt-table-checksum/bugs.t	2012-10-08 18:50:28 +0000
@@ -176,6 +176,22 @@
 );
 
 # #############################################################################
+# pt-table-checksum can crash with --columns if none match
+# https://bugs.launchpad.net/percona-toolkit/+bug/1016131
+# #############################################################################
+
+($output) = full_output(
+   sub { pt_table_checksum::main(@args, '--tables', 'mysql.user,mysql.host',
+                                 '--columns', 'some_fale_column') },
+);
+
+like(
+   $output,
+   qr/\QSkipping table mysql.user because all columns are excluded by --columns or --ignore-columns/,
+   "Bug 1016131: ptc should skip tables where all columns are excluded"
+);
+
+# #############################################################################
 # Done.
 # #############################################################################
 $sb->wipe_clean($master_dbh);
 
=== modified file 't/pt-table-checksum/run_time.t'
--- t/pt-table-checksum/run_time.t	2012-07-18 16:07:27 +0000
+++ t/pt-table-checksum/run_time.t	2012-10-08 18:50:28 +0000
@@ -38,16 +38,16 @@
 my $output;
 my $exit_status;
 
-# On my 2.4 GHz with SSD this takes a little more than 3s,
+# On my 2.4 GHz with SSD this takes a little more than 5s,
 # so no test servers should be faster, hopefully.
 my $t0 = time;
 $exit_status = pt_table_checksum::main(@args,
-   qw(--quiet --quiet -d sakila --chunk-size 100 --run-time 1));
+   qw(--quiet --quiet -d sakila --chunk-size 50 --run-time 1));
 my $t  = time - $t0;
 
 ok(
-   $t >= 1.5 && $t <= 2.0,
-   "Run in roughly --run-time 1 second"
+   $t >= 1.5 && $t <= 2.5,
+   "Ran in roughly --run-time 1 second"
 ) or diag("Actual run time: $t");
 
 my $rows = $master_dbh->selectall_arrayref("SELECT DISTINCT CONCAT(db, '.', tbl) FROM percona.checksums ORDER by db, tbl");