PT-2295 - Fix tests on distributions

- Fixed sporadic pt-tc failures on rolled back SHOW MASTER STATUS code
- Added better diagnostic info for sporadically failing t/pt-table-checksum/basics.t
- Decreased chunk size it t/pt-table-checksum/progress.t, so this test
  has less chances to fail, because pt-osc finishes faster than expected

bin/pt-table-checksum

@@ -5604,8 +5604,14 @@ sub get_master_status {
       return;
    }
 
-   my $sth = $self->{sths}->{$dbh}->{MASTER_STATUS}
+   my $sth;
+   if ( $self->{sths}->{$dbh} && $dbh && $self->{sths}->{$dbh} == $dbh ) {
+      $sth = $self->{sths}->{$dbh}->{MASTER_STATUS}
          ||= $dbh->prepare('SHOW MASTER STATUS');
+   }
+   else {
+      $sth = $dbh->prepare('SHOW MASTER STATUS');
+   }
    PTDEBUG && _d($dbh, 'SHOW MASTER STATUS');
    $sth->execute();
    my ($ms) = @{$sth->fetchall_arrayref({})};

lib/MasterSlave.pm

@@ -538,8 +538,14 @@ sub get_master_status {
       return;
    }
 
-   my $sth = $self->{sths}->{$dbh}->{MASTER_STATUS}
+   my $sth;
+   if ( $self->{sths}->{$dbh} && $dbh && $self->{sths}->{$dbh} == $dbh ) {
+      $sth = $self->{sths}->{$dbh}->{MASTER_STATUS}
          ||= $dbh->prepare('SHOW MASTER STATUS');
+   }
+   else {
+      $sth = $dbh->prepare('SHOW MASTER STATUS');
+   }
    PTDEBUG && _d($dbh, 'SHOW MASTER STATUS');
    $sth->execute();
    my ($ms) = @{$sth->fetchall_arrayref({})};

lib/bash/collect.sh

@@ -317,6 +317,8 @@ collect_system_data_loop() {
    # Sleep between collect cycles.
    # Synchronize ourselves onto the clock tick, so the sleeps are 1-second
    sleep $(date +'%s.%N' | awk "{print $OPT_SLEEP_COLLECT - (\$1 % $OPT_SLEEP_COLLECT)}")
+   log "In collect_system_data_loop"
+   log  $(date +'%s.%N' | awk "{print $OPT_SLEEP_COLLECT - (\$1 % $OPT_SLEEP_COLLECT)}")
    ts="$(date +"TS %s.%N %F %T")"
 
    # #####################################################################

t/lib/bash/collect.sh

@@ -173,6 +173,25 @@ parse_options "$BIN_DIR/pt-stalk" --run-time 2 -- --defaults-file=/tmp/12345/my.
 
 rm $PT_TMPDIR/collect/*
 
+collect "$PT_TMPDIR/collect" "2011_12_05" > $p-output 2>&1
+
+cat $p-output
+
+iters=$(cat $p-df | grep -c '^TS ')
+is "$iters" "2" "2 iteration/2s run time"
+
+if [ -f "$p-vmstat" ]; then
+   n=$(awk '/[ ]*[0-9]/ { n += 1 } END { print n }' "$p-vmstat")
+   is \
+      "$n" \
+      "2" \
+      "vmstat runs for --run-time seconds (bug 955860)"
+else
+   is "1" "1" "SKIP vmstat not installed"
+fi
+
+rm $PT_TMPDIR/collect/*
+
 fake_opcontrol="$PT_TMPDIR/collect/fake_opcontrol"
 fake_out="$PT_TMPDIR/collect/pt-faked-opcontrol-out"
 cat <<FAKE_EXEC > "$fake_opcontrol"
@@ -192,25 +211,13 @@ collect "$PT_TMPDIR/collect" "2011_12_05" > $p-output 2>&1
 CMD_OPCONTROL=""
 OPT_COLLECT_OPROFILE=""
 
-cat $p-df | grep -c '^TS '
-iters=$(cat $p-df | grep -c '^TS ')
-is "$iters" "2" "2 iteration/2s run time"
-
 is \
    "$(cat "$fake_out")" \
    "Faked opcontrol: --init" \
    "Bug 986847: Can manually set which commands pt-stalk uses"
 
-if [ -f "$p-vmstat" ]; then
-   n=$(awk '/[ ]*[0-9]/ { n += 1 } END { print n }' "$p-vmstat")
-   is \
-      "$n" \
-      "2" \
-      "vmstat runs for --run-time seconds (bug 955860)"
-else
-   is "1" "1" "SKIP vmstat not installed"
-fi
-
 # ############################################################################
 # Done
 # ############################################################################
+
+rm $PT_TMPDIR/collect/*

t/pt-table-checksum/basics.t

@@ -85,16 +85,18 @@ sub reset_repl_db {
 # So we will re-run failed code if test does not pass.
 my $cmd = sub { pt_table_checksum::main(@args) };
 
-diag(output($cmd)) if not ok(
+#diag(output($cmd)) 
+ok(
    no_diff(
       $cmd,
       "$sample/default-results-$sandbox_version.txt",
       sed_out => '\'/mysql.plugin$/d; /percona_test.checksums$/d; /mysql.help_category$/d; /mysql.help_keyword$/d; /mysql.help_relation$/d; /mysql.help_topic$/d\'',
       post_pipe => 'sed \'/mysql.plugin$/d; /percona_test.checksums$/d; /mysql.help_category$/d; /mysql.help_keyword$/d; /mysql.help_relation$/d; /mysql.help_topic$/d; /mysql.ndb_binlog_index$/d; /mysql.global_grants$/d\' | ' .
                    'awk \'{print $2 " " $3 " " $4 " " $7 " " $9}\'',
+      keep_ouput => 1,
    ),
    "Default checksum"
-);
+) or diag($test_diff);
 
 # On fast machines, the chunk size will probably be be auto-adjusted so
 # large that all tables will be done in a single chunk without an index.

t/pt-table-checksum/progress.t

@@ -48,7 +48,7 @@ else {
 # worse. This is a random stab in the dark. There is a problem either way.)
 my $master_dsn = 'h=127.1,P=12345,u=msandbox,p=msandbox';
 my @args       = ($master_dsn, qw(--set-vars innodb_lock_wait_timeout=3),
-                   '--chunk-size', '200'); 
+                   '--chunk-size', '50'); 
 my $output;
 my $row;
 my $scripts = "$trunk/t/pt-table-checksum/scripts/";
@@ -83,7 +83,7 @@ like(
    $output,
    qr/Replica h=127.0.0.1,P=12347 is stopped/,
    "--progress for slave lag"
-);
+) or diag($output);
 
 like(
    $output,