added --skip-check-slave-lag

bin/pt-online-schema-change

@@ -8508,9 +8508,31 @@ sub main {
          $slave_lag_cxns = $slaves;
       }
       if ( $slave_lag_cxns && scalar @$slave_lag_cxns ) {
-         print "Will check slave lag on:\n";
+         if ($o->get('skip-check-slave-lag')) {
-         foreach my $cxn ( @$slave_lag_cxns ) {
+             my $slaves_to_skip = $o->get('skip-check-slave-lag');
-            print "  " . $cxn->name() . "\n";
+             my $filtered_slaves = [];
+             for my $slave (@$slave_lag_cxns) {
+                 my $found=0;
+                 for my $slave_to_skip (@$slaves_to_skip) {
+                     if ($slave->{dsn}->{h} eq $slave_to_skip->{h} && $slave->{dsn}->{P} eq $slave_to_skip->{P}) {
+                         $found=1;
+                     }
+                 }
+                 if ($found) {
+                    printf("Skipping slave %s -> %s:%s\n", $slave->name(), $slave->{dsn}->{h}, $slave->{dsn}->{P});
+                 } else {
+                    push @$filtered_slaves, $slave;
+                 }
+             }
+             $slave_lag_cxns = $filtered_slaves;
+         }
+         if (!scalar @$slave_lag_cxns) {
+            print "Not checking slave lag because all slaves were skipped\n";
+         } else{
+            print "Will check slave lag on:\n";
+            foreach my $cxn ( @$slave_lag_cxns ) {
+               printf("%s -> %s:%s\n", $cxn->name(), $cxn->{dsn}->{h}, $cxn->{dsn}->{P});
+            }
          }
       }
       else {

bin/pt-table-checksum

@@ -9681,11 +9681,40 @@ sub main {
             0;
          }
          else {
-            PTDEBUG && _d('Will check slave lag on', $slave_cxn->name());
+            PTDEBUG && _d('May check slave lag on', $slave_cxn->name());
             $slave_cxn;
          }
       } @$slave_lag_cxns;
 
+      if ( $slave_lag_cxns && scalar @$slave_lag_cxns ) {
+         if ($o->get('skip-check-slave-lag')) {
+             my $slaves_to_skip = $o->get('skip-check-slave-lag');
+             my $filtered_slaves = [];
+             for my $slave (@$slave_lag_cxns) {
+                 my $found=0;
+                 for my $slave_to_skip (@$slaves_to_skip) {
+                     if ($slave->{dsn}->{h} eq $slave_to_skip->{h} && $slave->{dsn}->{P} eq $slave_to_skip->{P}) {
+                         $found=1;
+                     }
+                 }
+                 if ($found) {
+                    printf("Skipping slave %s -> %s:%s\n", $slave->name(), $slave->{dsn}->{h}, $slave->{dsn}->{P});
+                 } else {
+                    push @$filtered_slaves, $slave;
+                }
+             }
+             $slave_lag_cxns = $filtered_slaves;
+         }
+      }
+
+      if ( $slave_lag_cxns && scalar @$slave_lag_cxns ) {
+         for my $slave (@$slave_lag_cxns) {
+            printf("Checking lag on %s -> %s:%s\n", $slave->name(), $slave->{dsn}->{h}, $slave->{dsn}->{P});
+        }
+      } else {
+          print "Not checking slave lag because no slaves were found or they were set to be skipped\n";
+      }
+
       # #####################################################################
       # Possibly check replication slaves and exit.
       # #####################################################################
@@ -12701,6 +12730,13 @@ type: string; default: #
 The separator character used for CONCAT_WS().  This character is used to join
 the values of columns when checksumming.
 
+=item --skip-check-slave-lag
+
+type: DSN; repeatable: yes
+
+DSN to skip when checking slave lag. It can be used multiple times.
+Example: --skip-check-slave-lag h=127.1,P=12345 --skip-check-slave-lag h=127.1,P=12346
+
 =item --slave-user
 
 type: string

lib/Sandbox.pm

@@ -483,6 +483,7 @@ sub start_sandbox {
 
    if ( $type eq 'master') {
       my $out = `$env $trunk/sandbox/start-sandbox $type $port`;
+      warn "$env";
       die $out if $CHILD_ERROR;
    }
    elsif ( $type eq 'slave' ) {

sandbox/start-sandbox

@@ -39,7 +39,9 @@ make_sandbox() {
    rm -rf /tmp/$port || die "Failed to rm /tmp/$port"
    mkdir /tmp/$port  || die "Failed to mkdir /tmp/$port"
    cp $PERCONA_TOOLKIT_BRANCH/sandbox/servers/${APP#mysql}/$version/my.sandbox.cnf /tmp/$port
-   tar xzf $PERCONA_TOOLKIT_BRANCH/sandbox/servers/${APP#mysql}/$version/data.tar.gz -C /tmp/$port
+   if [ -e $PERCONA_TOOLKIT_BRANCH/sandbox/servers/${APP#mysql}/$version/data.tar.gz ]; then
+      tar xzf $PERCONA_TOOLKIT_BRANCH/sandbox/servers/${APP#mysql}/$version/data.tar.gz -C /tmp/$port
+   fi
 
    for script in "$PERCONA_TOOLKIT_BRANCH/sandbox/servers/"*; do
       if [ -f $script ]; then
@@ -244,6 +246,7 @@ else
 fi
 
 APP="${FORK:-"mysql"}"
+echo "APP $APP" > /home/karl/k
 
 if [ $type = "cluster" -o $APP = "pxc" ]; then
 # disabled for now because used perl module is not available everywhere and in some distros it returns ipv6 address
@@ -253,6 +256,7 @@ if [ $type = "cluster" -o $APP = "pxc" ]; then
 else
    version=`$PERCONA_TOOLKIT_SANDBOX/$mysqld -V 2>/dev/null | awk '{print $3}' | cut -d. -f 1,2`;
 fi
+echo "version $version" >> /home/karl/k
 
 if [ ! -d "$PERCONA_TOOLKIT_BRANCH/sandbox/servers/${APP#mysql}/$version" ]; then
    die "$PERCONA_TOOLKIT_BRANCH/sandbox/servers/${APP#mysql}/$version does not exist."

t/pt-online-schema-change/issue-1638293.t

@@ -22,6 +22,10 @@ require "$trunk/bin/pt-online-schema-change";
 my $dp = new DSNParser(opts=>$dsn_opts);
 my $sb = new Sandbox(basedir => '/tmp', DSNParser => $dp);
 
+if ( !$sb->is_cluster_mode ) {
+   plan skip_all => 'Only for PXC',
+}
+
 my ($master_dbh, $master_dsn) = $sb->start_sandbox(
    server => 'cmaster',
    type   => 'master',

t/pt-table-checksum/bugs.t

@@ -184,9 +184,9 @@ $output = output(
 
 chomp($output);
 
-is(
+like(
    $output,
-   '',
+   qr/Checking lag on h=127.0.0.1,P=12346 -> 127.0.0.1:12346/,
    "Bug 1074179: ignore-tables-regex works with --replicate-check-only"
 );
 # #############################################################################
@@ -206,6 +206,22 @@ like(
    "Bug 1016131: ptc should skip tables where all columns are excluded"
 );
 
+# Test #12
+{
+$output = output(
+   sub { pt_table_checksum::main(@args, 
+         '--skip-check-slave-lag', "h=127.0.0.1,P=".$sb->port_for('slave1'),
+         ),
+      },
+);
+
+my $skipping_str = "Skipping.*".$sb->port_for('slave1');
+like(
+      $output,
+      qr/$skipping_str/s,
+      "--skip-check-slave-lag",
+);
+}
 # #############################################################################
 # Illegal division by zero at pt-table-checksum line 7950
 # https://bugs.launchpad.net/percona-toolkit/+bug/1075638
@@ -319,6 +335,7 @@ diag(`/tmp/12346/stop >/dev/null`);
 diag(`/tmp/12346/start >/dev/null`); 
 
 
+#
 # #############################################################################
 # Done.
 # #############################################################################