ljr/livejournal/bin/ljumover.pl

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2019-02-05 21:49:12 +00:00
#!/usr/bin/perl
##############################################################################
=head1 NAME
umover - User shuffling daemon
=head1 SYNOPSIS
$ umover OPTIONS MOVECOMMAND
$ umover OPTIONS COMMANDFILE
$ umover --unlock
=head2 OPTIONS
=over 4
=item -h, --help
Output a help message and exit.
=item -d, --debug
Output debugging information in addition to normal progress messages.
=item -t, --test
Just test the mover code, don't actually move anyone.
=item -v, --verbose
Output verbose progress information.
=item -T, --threads=<count>
Specify how many threads (subprocesses) to start with for the move. Settings in
C<$ENV{LJHOME}/var/mover-workers> are overridden by this setting.
=item -u,--unlock
Run a query against the mover's "in-progress" table, confirming movers listed
there are still active. This can be run either standalone (i.e., with no
I<MOVECOMMAND> or I<COMMANDFILE>, or as part of a mover run, in which case it
will do an unlock cycle before starting to move anything itself.
=head2 MOVECOMMAND
Move commands are in the form:
<src clusters>[+active[(<number>)]] to <dest clusters> [<max users>]
=over 4
=item B<src clusters>
A comma-delimited list of clusters or cluster ranges from which to move
users.
Example:
30-33, 35, 39
=item B<+active>
If this option is given, only active users will be moved. You can specify the
number of days to consider "active" by appending a number in parentheses, e.g.,
active(20)
means that "active" means activity within the last 20 days. If not specified,
the default of 30 is used.
=item B<dest clusters>
Like B<src clusters>, another comma-delimited list of clusters or cluster
ranges, but specifying the clusters which users will be moved to.
=item B<max users>
A number which serves as an upper limit on the number of users to move in this
run.
=back
=head2 Examples
Move active users from clusters 30-33, 35, and 39 to clusters 40-45.
30-33, 35, 39 +active to 40-45
Move 10000 users from cluster 18 to clusters 20-24, distributing them evenly
between destination clusters.
18 to 20-24 10000
=head2 COMMANDFILE
This is the name of a file that contains one or more of the above
L<MOVECOMMAND>s. Each line will be executed in turn.
=head1 REQUIRES
I<Token requires line>
=head1 DESCRIPTION
This is a command-line tool which does mass user-move operations between various
clusters. It just drives multiple invocations of $LJHOME/bin/moveucluster.pl.
=head1 AUTHOR
Michael Granger E<lt>ged@FaerieMUD.orgE<gt>
Copyright (c) 2003 Danga Interactive. All rights reserved.
=cut
##############################################################################
package umover;
use strict;
use warnings qw{all};
###############################################################################
### I N I T I A L I Z A T I O N
###############################################################################
BEGIN {
# Turn STDOUT buffering off
$| = 1;
# Versioning stuff and custom includes
use vars qw{$VERSION $RCSID $AUTOLOAD};
$VERSION = do { my @r = (q$Revision: 1.14 $ =~ /\d+/g); sprintf "%d."."%02d" x $#r, @r };
$RCSID = q$Id: ljumover.pl,v 1.14 2004/02/13 07:24:32 avva Exp $;
# Define some constants
use constant TRUE => 1;
use constant FALSE => 0;
# Modules
use Getopt::Long qw{GetOptions};
use Pod::Usage qw{pod2usage};
use IO::File qw{};
use Fcntl qw{O_RDONLY};
use Digest::MD5 qw{md5_base64};
use Data::Dumper qw{};
use IO::Socket qw{};
use Sys::Hostname qw{hostname};
use Time::HiRes qw{gettimeofday};
# LiveJournal functions
require "$ENV{'LJHOME'}/cgi-bin/ljlib.pl";
# Turn on option bundling (-vid)
Getopt::Long::Configure( "bundling" );
$Data::Dumper::Terse = 1;
$Data::Dumper::Indent = 0;
}
sub runCommand ($$$$$$);
sub parseCommand ($);
sub parseCluster ($);
sub cleanup ();
sub unlockStaleUsers ();
sub startDaemon ();
sub daemonRoutine ($$);
sub abort (@);
###############################################################################
### C O N F I G U R A T I O N G L O B A L S
###############################################################################
our (
$Debug, $VerboseFlag, $ClusterSpecRe, $CommandRe,
$ReadOnlyBit, $DaemonPid, $MoverWorkersFile, $ActiveDaysDefault,
);
# -d and -v option flags
$Debug = FALSE;
$VerboseFlag = FALSE;
# Patterns for matching movement commands
$ClusterSpecRe = qr{
\d+ # Lead num
(?:\s*-\s*\d+)? # Range end num (optional)
(?:\s*,\s*)? # Comma + whitespace
}x;
$CommandRe = qr{^
($ClusterSpecRe+) # Source clusters
\s*
(\+\s*active
(?:\s*\(\s*\d+\s*\))? # Optional day-range
)? # Active flag
\s+
to # Literal 'to'
\s+
($ClusterSpecRe+) # Dest clusters
(?:\s+(\d+))? # Maximum
$}ix;
# Find the readonly cap class, complain if not found
BEGIN {
foreach my $bit ( keys %LJ::CAP ) {
$ReadOnlyBit = $bit, last
if $LJ::CAP{$bit}{_name} eq '_moveinprogress' &&
$LJ::CAP{$bit}{readonly} == 1;
}
die( "Won't move user without \%LJ::CAP capability class named ",
"'_moveinprogress' with readonly => 1\n" )
unless defined $ReadOnlyBit;
}
# The PID of the distributed lock daemon
$DaemonPid = undef;
# The path to the file that controls the number of running threads.
$MoverWorkersFile = "$ENV{LJHOME}/var/mover-workers";
# The number of days to use as the threshold for activity if the "+active" flag
# is given.
$ActiveDaysDefault = 30;
### Main body
MAIN: {
my (
$helpFlag, # User requested help?
$testingMode, # Test-only mode
$command, # Command iterator
$usercount, # Total users moved
$threads, # The number of threads to use while moving
$unlockMode, # Run an unlock cycle?
$instanceId, # The unique instance id of this mover
$daemonPid, # The pid of the distributed lock daemon
$daemonIp, # The IP the daemon is listening on
$daemonPort, # The ephemeral port the daemon is listening on
$ifh, # Input filehandle
@commands, # Move commands
);
GetOptions(
'd|debug+' => \$Debug,
'v|verbose' => \$VerboseFlag,
'h|help' => \$helpFlag,
't|test' => \$testingMode,
'T|threads=i' => \$threads,
'u|unlock' => \$unlockMode,
) or abortWithUsage();
# If the -h flag was given, just show the usage and quit
helpMode() and exit if $helpFlag;
verboseMsg( "Starting up." );
$usercount = 0;
DBI->trace( $Debug - 1 ) if $Debug >= 2;
unlockStaleUsers() if $unlockMode;
# Load the commands from a command file
if ( @ARGV == 1 && -f $ARGV[0] ) {
debugMsg( "Command-file mode." );
$ifh = IO::File->new( $ARGV[0], O_RDONLY )
or abort( "open: $ARGV[0]: $!" );
while ($command = ($ifh->getline)) {
next if $command =~ m{^\s*(#.*)?$};
push @commands, $command;
}
}
# Commands specified on the command line
elsif ( @ARGV && $ARGV[0] =~ m{^[\d]} ) {
debugMsg( "Command-line mode." );
@commands = @ARGV;
}
# If -u was given, it's okay to not given any commands
elsif ( $unlockMode ) {
exit;
}
else {
abortWithUsage( "Missing or malformed command string/s." );
}
( $instanceId, $daemonIp, $daemonPort ) = startDaemon();
# Set signal handlers
$SIG{HUP} = sub { abort "Caught SIGHUP." };
$SIG{INT} = sub { abort "Interrupted." };
$SIG{TERM} = sub { abort "Terminated." };
# Now run the given move commands
foreach my $command ( @commands ) {
$usercount += runCommand( $command, $testingMode, $threads,
$instanceId, $daemonIp, $daemonPort );
}
# Run any needed cleanup functions
cleanup();
message( "Done with all commands. $usercount users moved." );
}
### FUNCTION: cleanup()
### Clean up any children that are still running.
sub cleanup () {
kill 'TERM', $DaemonPid;
}
#####################################################################
### D A E M O N ( M U L T I - M O V E R ) F U N C T I O N S
#####################################################################
### FUNCTION: unlockStaleUsers()
### Traverse the clustermove_inprogress table, confirming that each entry
### belongs to an active mover, removing those that don't.
sub unlockStaleUsers () {
my (
$sql, # SQL query source
$dbh, # Database handle (writer)
$selsth, # SELECT statement handle
$delsth, # DELETE statement handle
$row, # Selected row hashref
$sock, # Query socket
%cachedReply, # Cached replies: {$instance => $bool} (running or not)
);
verboseMsg( "Cleaning up the in-progress table." );
$sql = q{
SELECT *
FROM clustermove_inprogress
};
# Get a select cursor for the in-progress table
$dbh = LJ::get_db_writer() or abort( "Couldn't fetch a database handle." );
$selsth = $dbh->prepare( $sql )
or abort( "prepare: $sql: ", $dbh->errstr );
$selsth->execute or abort( "execute: $sql: ", $selsth->errstr );
# Get a deletion cursor for it too.
$sql = q{
DELETE FROM clustermove_inprogress
WHERE userid = ?
};
$delsth = $dbh->prepare( $sql )
or abort( "prepare: $sql: ", $dbh->errstr );
$delsth->{ShowErrorStatement} = 1;
# Fetch each record, connecting to the given host/port for each
# moverinstance and deleting users for those found not to be running.
while (( $row = $selsth->fetchrow_hashref )) {
my ( $host, $port, $instance, $userid ) =
@{$row}{'moverhost','moverport','moverinstance','userid'};
my $ip = join '.',
reverse map { ($host >> $_ * 8) & 0xff } 0..3;
# If the host hasn't been contacted yet, do so now
if ( !exists $cachedReply{$instance} ) {
debugMsg( "Contacting mover at %s:%d (%s) for user %d",
$ip, $port, $instance, $userid );
# If the connection succeeds and replies with the correct response,
# then the entry's okay
if (( $sock = new IO::Socket::INET("$ip:$port") )) {
my $reply = $sock->getline;
$sock->close;
debugMsg( "Got reply '%s' from mover at %s:%d", $reply, $host, $port );
$cachedReply{$instance} = ($instance eq $reply ? 1 : 0);
}
# Connection error
else {
debugMsg( "Couldn't open a socket to $ip:$port: $!" );
$cachedReply{$instance} = '';
}
}
# If the cached value indicates it's an invalid record, delete it.
if ( !$cachedReply{$instance} ) {
debugMsg( "Removing stale lock set by %s:%d on %s for uid %d",
$host, $port, scalar localtime($row->{locktime}), $userid );
LJ::update_user( $row->{user}, {raw => "caps=caps^(1<<$ReadOnlyBit)"} );
$delsth->execute( $userid )
or abort( "execute: $userid: ", $delsth->errstr );
} else {
debugMsg( "Keeping lock set by %s:%d on %s for uid %d",
$host, $port, scalar localtime($row->{locktime}), $userid );
}
}
$delsth->finish;
$selsth->finish;
return 1;
}
### FUNCTION: startDaemon()
### Start a daemon process on an ephemeral port to support distributed
### moves. This function returns a list which consists of an I<instanceId>, the
### ip address of the listener, and the port of the listener. The I<instanceId>,
### which is a 22-character-long (e.g., MD5 hash in base64) string which
### uniquely identifies this instance, should be used in the 'moverinstance'
### field of the clustermove_inprogress' table when locking users for
### moving. When anything connects to the opened port, the daemon writes its
### I<instanceId> to the socket and shuts the socket down. This function also
### sets $DaemonPid to the process id of the forked child.
sub startDaemon () {
my (
$seed, # The source string for the instance id
$id, # The instance id
$lsock, # Locking socket
$host, # Hostname to listen on
$ip, # The ip of the listener socket
$port, # The port number the listener socket is listening to
);
verboseMsg( "Starting distributed lock daemon." );
# Create the "instance id"
$seed = join( ':', $$, (gettimeofday), hostname );
$id = md5_base64( $seed );
# Create the listener socket
$host = hostname();
$lsock = new IO::Socket::INET(
Listen => 4,
LocalAddr => $host,
#LocalPort => 0, # Kernel chooses ephemeral port
Reuse => 1 ) # SO_REUSEADDR
or abort( "Could not open listener socket: $!" );
$ip = sprintf '%vd', $lsock->sockaddr;
$port = $lsock->sockport;
if (( $DaemonPid = fork )) {
debugMsg( "Started daemon (%d) at %s:%d with id = '%s'",
$DaemonPid, $ip, $port, $id );
$lsock->close;
}
else {
LJ::disconnect_dbs();
daemonRoutine( $lsock, $id );
exit;
}
return ( $id, $ip, $port );
}
### FUNCTION: daemonRoutine( $socket, $instanceId )
### Listen to the given I<socket>, writing the specified I<instanceId> to any
### connecting client.
sub daemonRoutine ($$) {
my ( $listener, $id ) = @_;
while (( my $sock = $listener->accept )) {
$sock->print( $id );
$sock->shutdown( 2 );
}
}
#####################################################################
### M O V E R F U N C T I O N S
#####################################################################
### FUNCTION: runCommand( $cmd )
### Parse the given command and run it, returning the numebr of users that were
### moved.
sub runCommand ($$$$$$) {
my ( $commandStr, $testingMode, $maxThreads, $id, $ip, $port ) = @_;
my (
$cmd,
$mover,
$count,
);
debugMsg( "Parsing command '$commandStr'." );
$cmd = parseCommand( $commandStr );
debugMsg( "Parsed command: %s", $cmd );
$mover = new Mover (
sources => $cmd->{sources},
dests => $cmd->{dests},
max => $cmd->{max},
activeUsersOnly => $cmd->{active},
activeDays => $cmd->{activeDays} || $ActiveDaysDefault,
chunksize => 500,
debugFunction => \&debugMsg,
messageFunction => \&verboseMsg,
testingMode => $testingMode,
maxThreads => $maxThreads,
instanceId => $id,
lockIp => $ip,
lockPort => $port,
);
message( 'Moving users%s: %s',
$testingMode ? " (testing mode)" : "", $mover->desc );
$count = $mover->start;
message( 'Done with %s: %d users.',
$mover->desc, $count );
return $count;
}
### FUNCTION: parseCommand( $cmd )
### Parse the specified command into a usable command spec, which is returned as
### a hashref.
sub parseCommand ($) {
my $command = shift or die "No command specified";
my (
$srcClusters,
@sources,
$activeFlag,
$activeDays,
$dstClusters,
@dests,
$max,
);
unless ( $command =~ $CommandRe ) {
abort( "Could not parse command '$command'" );
return undef;
}
( $srcClusters, $activeFlag, $dstClusters, $max ) = ( $1, $2, $3, $4 );
debugMsg( "Matched: %s", [$srcClusters, $activeFlag, $dstClusters, $max] );
# Parse source clusters
foreach my $cluster ( split(/\s*,\s*/, $srcClusters) ) {
push @sources, parseCluster( $cluster );
}
# Parse destination clusters
foreach my $cluster ( split(/\s*,\s*/, $dstClusters) ) {
push @dests, parseCluster( $cluster );
}
# Grab the "days" param from the "active" flag if both were present
if ( $activeFlag && $activeFlag =~ m{(\d+)} ) {
$activeDays = int( $1 );
}
my $rval = {
sources => \@sources,
active => $activeFlag ? TRUE : FALSE,
activeDays => $activeDays,
dests => \@dests,
max => $max || 0,
};
debugMsg( "Parsed command '%s' into: %s", $command, $rval );
return $rval;
}
### FUNCTION: parseCluster( $clusterSpec )
### Parse the given I<clusterSpec> into an list of cluster numbers and return
### them.
sub parseCluster ($) {
my $cluster = shift;
die "No cluster specified" unless defined $cluster;
my @rval = ();
$cluster =~ s{\s+}{}g;
if ( $cluster =~ m{^(\d+)-(\d+)$} ) {
push @rval, ($1 .. $2);
} elsif ( $cluster =~ m{^(\d+)$} ) {
push @rval, $1;
} else {
error( "Unable to parse cluster: $cluster" );
}
debugMsg( "Parsed cluster '%s' into: %s", $cluster, \@rval );
return @rval;
}
### Kill the daemon process if it's defined and alive
END {
if ( $DaemonPid ) {
kill 'TERM', $DaemonPid;
}
}
#####################################################################
### U T I L I T Y F U N C T I O N S
#####################################################################
### FUNCTION: helpMode()
### Exit normally after printing the usage message
sub helpMode {
pod2usage( -verbose => 1, -exitval => 0 );
}
### FUNCTION: abortWithUsage( $message )
### Abort the program showing usage message.
sub abortWithUsage {
my $msg = join '', @_;
if ( $msg ) {
pod2usage( -verbose => 1, -exitval => 1, -message => "$msg" );
} else {
pod2usage( -verbose => 1, -exitval => 1 );
}
}
### FUNCTION: message( @messages )
### Concatenate and print the specified messages.
sub message {
my ( $format, @args ) = @_;
printf STDERR "$format\n", @args;
}
### FUNCTION: verboseMsg( @messages )
### Concatenate and print the specified messages if verbose output is turned on.
sub verboseMsg {
return unless $VerboseFlag;
message( @_ );
}
### FUNCTION: error( @messages )
### Print the specified messages to the terminal's STDERR.
sub error {
my $message = @_ ? join '', @_ : '[Mark]';
print STDERR "ERROR >>> $message <<<\n";
}
### FUNCTION: debugMsg( @messages )
### Print the specified messages to the terminal if debugging mode is activated.
sub debugMsg {
return unless $Debug;
my $format = shift;
chomp( $format );
my @args = map {
ref $_
? Data::Dumper->Dumpxs([$_])
: $_;
} @_;
my $message = sprintf( $format, @args );
print STDERR "DEBUG> $message\n";
}
### FUNCTION: abort( @messages )
### Print the specified messages to the terminal and exit with a non-zero status.
sub abort (@) {
my $msg = @_ ? join '', @_ : "unknown error";
print STDERR "Aborted: $msg.\n\n";
exit 1;
}
#####################################################################
### M O V E R C L A S S
#####################################################################
package Mover;
BEGIN {
# LiveJournal functions
require "$ENV{'LJHOME'}/cgi-bin/ljlib.pl";
use vars qw{$AUTOLOAD};
use Carp qw{confess croak};
use Time::HiRes qw{usleep};
use POSIX qw{:sys_wait_h};
}
### METHOD: new( %args )
### Create a new Mover object configured with the given I<args>.
sub new {
my $class = shift;
my %args = @_;
my $self = bless {
sources => [],
dests => [],
max => 0,
activeUsersOnly => 0,
activeDays => 30,
chunksize => 500,
maxThreads => 0,
moverWorkersMtime => 0,
userThreads => {},
activeThreads => {},
fakeMovedUsers => {},
debugFunction => undef,
messageFunction => undef,
debugMode => 0,
instanceId => undef,
lockIp => undef,
lockPort => undef,
_signals => {},
_haltFlag => 0,
_shutdownFlag => 0,
_lastStat => 0,
%args,
}, $class;
return $self;
}
### METHOD: desc()
### Return a description of the lock object.
sub desc {
my $self = shift or confess "Cannot be called as a function";
return sprintf( '[%s]%s -> [%s] (Max: %s, Chunksize: %d)',
join(',', @{$self->{sources}}),
$self->{activeUsersOnly}
? " (Active $self->{activeDays} days)"
: "",
join(',', @{$self->{dests}}),
$self->max,
$self->chunksize,
);
}
### METHOD: debugMsg( @args )
### If the 'debugFunction' attribute of the mover object is set, call it with
### the specified I<args>.
sub debugMsg {
my $self = shift or confess "Cannot be called as a function";
return unless $self->{debugFunction};
$self->{debugFunction}( @_ );
}
### METHOD: message( @args )
### If the 'messageFunction' attribute of the mover object is set, call it with
### the specified I<args>.
sub message {
my $self = shift or confess "Cannot be called as a function";
return unless $self->{messageFunction};
$self->{messageFunction}( @_ );
}
### METHOD: start( [$max] )
### Start moving users. If I<max> is specified, quit after the specified number
### are moved. Returns the number of users moved.
sub start {
my $self = shift or confess "Cannot be called as a function";
my (
$maxUsers,
$count,
$scale,
$maxThreads,
$oldMax,
$chunksize,
@users,
@queue,
$thread,
$uid,
$pid,
$dest,
$dbh,
);
$maxUsers = $self->max || 1e+33;
$maxThreads = $oldMax = $self->{maxThreads};
$chunksize = $self->chunksize;
$chunksize = $maxUsers if $maxUsers < $chunksize;
$count = 0;
$self->setSignalHandlers;
# Iterate over all users for this worker's cluster list, $chunksize per
# cluster at a time.
USER: while ( !$self->{_haltFlag} && !$self->{_shutdownFlag} && $count < $maxUsers )
{
# Re-read the thread config each time
$maxThreads = $self->getMaxThreads( $maxThreads );
$self->debugMsg( "User loop: max threads: $maxThreads" );
# Advise the use if the thread count changes.
if ( defined $oldMax && $maxThreads != $oldMax ) {
$self->message( "Set thread count to %d (was %d)", $maxThreads, $oldMax );
$oldMax = $maxThreads;
}
# No need to do any of the rest if there's no threads to run 'em.
unless ( $maxThreads ) {
$self->message( "Idling (threads = 0)." );
$self->reapChildren;
sleep 10;
next USER;
}
# Fetch users if the buffer isn't already populated
unless ( @users ) {
@users = $self->getPendingUsers( $chunksize )
or last USER;
$self->message( "Fetched %d pending users.", scalar @users );
}
# Splice off some users to prepare for moving. Never splice off more
# than the maximum number of users for this run
$scale = $maxThreads * 3;
$scale = ($maxUsers - $count) if ($count + $scale) > $maxUsers;
@queue = splice( @users, 0, $scale );
# Now wrap a thread object around each user in the queue, which also
# locks each one.
@queue = map {
my $userRecord = $_;
last USER if $self->{_haltFlag} || $self->{_shutdownFlag};
$dest = $self->pickDestination;
$self->debugMsg( "Creating a thread for user '%s' (%d -> %d)",
$userRecord->{user}, $userRecord->{clusterid},
$dest );
# Create a mover thread (sets the user's read-only bit).
$self->{userThreads}{$userRecord->{userid}} =
Mover::Thread->new( @{$userRecord}{'user','userid','clusterid'}, $dest );
} @queue;
# Wait for the read-only bit to sink in
$self->debugMsg( "Waiting for read-only bit to sink in." );
sleep 3;
# Iterate over the thread objects, forking each one off as the
# number of active ones falls below the maximum allowed.
THREAD: foreach my $thread ( @queue ) {
last USER if $self->{_haltFlag};
# Wait until more threads can be started
until ( keys %{$self->{activeThreads}} < $maxThreads ) {
last USER if $self->{_haltFlag} || $self->{_shutdownFlag};
$self->reapChildren;
usleep 0.5;
}
# Mark the user as "in progress" by setting the destination
# cluster field. :FIXME: This is obviously stupid to disconnect
# and reconnect every time, but since the handle is b0rked after
# the ->run() below fork()s, this is necessary for it to work.
LJ::disconnect_dbs();
$dbh = LJ::get_db_writer()
or die "Couldn't fetch a writer.";
$dbh->do(q{
UPDATE clustermove_inprogress SET dstclust = ? WHERE userid = ?
}, undef, $thread->dest, $thread->userid )
or die "Failed to update lock: ", $dbh->errstr;
# Run the thread
$count++;
$thread->testingMode( $self->testingMode );
$self->message( "Moving user '%s' (#%d): src %d -> dst %d (count: %d)",
$thread->user, $thread->userid, $thread->src,
$thread->dest, $count );
$pid = $thread->run;
$self->{activeThreads}{ $pid } = $thread;
$self->reapChildren;
}
$self->reapChildren;
}
if ( $self->{_haltFlag} ) { $self->message( ">>> Halted by signal <<<" ) }
elsif ( $self->{_shutdownFlag} ) { $self->message( ">>> Shutdown by signal <<<" ) }
else { $self->debugMsg( "Done with thread loop." ); }
$self->restoreSignalHandlers;
# Handle threads that are still running
if ( %{$self->{activeThreads}} ) {
# Let children finish unless the process is being forcefully shut down.
unless ( $self->{_haltFlag} ) {
foreach ( 1..10 ) {
last unless %{$self->{activeThreads}};
$self->message( "Waiting for %d remaining children to finish.",
scalar keys %{$self->{activeThreads}} );
$self->reapChildren;
sleep 1;
}
}
# Kill off any remaining children if there are any
foreach my $signal ( 'TERM', 'QUIT', 'KILL' ) {
last unless %{$self->{activeThreads}};
$self->message( "Sending SIG%s to remaining %d threads.",
$signal, scalar keys %{$self->{activeThreads}} );
foreach my $pid ( keys %{$self->{activeThreads}} ) {
kill $signal, $pid if exists $self->{activeThreads}{ $pid };
}
$self->reapChildren;
} continue {
sleep 2;
};
}
# Unlock any users that didn't get moved
if ( %{$self->{userThreads}} ) {
$self->message( "Unlocking %d remaining users.", values %{$self->{userThreads}} );
foreach my $thread ( values %{$self->{userThreads}} ) {
$thread->unlock;
LJ::disconnect_dbs();
my $dbh = LJ::get_db_writer() or die "Couldn't get a db_writer.";
$dbh->do( "DELETE FROM clustermove_inprogress WHERE userid = ?",
undef, $thread->userid )
or die "Failed to delete user ", $thread->userid,
" from the in-progress table: ", $dbh->errstr;
}
}
return $count;
}
### METHOD: reapChildren()
### Collect any child processes that have died. Returns the number of processed
### reaped.
sub reapChildren {
my $self = shift or confess "Cannot be called as a function";
my $count = 0;
# Reap any child processes that need it and delete the corresponding thread
# object from the thread table. Delete the user from the user => thread map
# unless the thread is in testing mode (ie., doesn't actually remove the
# user from the source table).
while ((my $pid = waitpid( -1, WNOHANG )) > 0) {
next if $pid == $DaemonPid;
my $thread = delete $self->{activeThreads}{ $pid };
$self->{fakeMovedUsers}{$thread->userid} = 1 if $thread->testingMode;
delete $self->{userThreads}{$thread->userid};
$thread->unlock;
LJ::disconnect_dbs();
my $dbh = LJ::get_db_writer() or die "Couldn't get a db_writer.";
$dbh->do( "DELETE FROM clustermove_inprogress WHERE userid = ?",
undef, $thread->userid )
or die "Failed to delete user ", $thread->userid,
" from the in-progress table: ", $dbh->errstr;
$self->debugMsg( "Reaped child %d (uid: %d, exit: %d). %d process/es remain.",
$pid, $thread->userid, $?,
scalar keys %{$self->{activeThreads}} );
$count++;
}
return $count;
}
### METHOD: pickDestination()
### Pick a destination cluster for the given user.
sub pickDestination {
my $self = shift or confess "Cannot be called as a function";
# Pick a destination, then rotate the list.
my $dest = $self->{dests}[0];
push( @{$self->{dests}}, shift @{$self->{dests}} );
return $dest;
}
### METHOD: getPendingUsers()
### Return users that need moving from the source clusters for this mover.
sub getPendingUsers {
my $self = shift or confess "Cannot be called as a function";
my $limit = shift || 500;
my (
$sql, # SQL query string
$dbh, # Database handle (writer)
$ipsth, # INSERT cursor for the in-progress table
$seldbh, # Database handle (cluster master for active users, copy of
# $dbh if not)
$selsth, # User-selection cursor
$iip, # Integer IP for insertion into the in-progress table
$row, # Row iterator
@users, # User rows
);
# :FIXME: This is the only way I can make this query work. If I don't do
# this, I get "MySQL has gone away" on the second query, despite calling
# disconnect_dbs() in the thread's start() method immediately after the
# fork(), too. Perhaps I'll revisit this after hacking on DBI::Role for a
# bit.
LJ::disconnect_dbs();
$dbh = LJ::get_db_writer() or die "failed to get_db_writer()";
$sql = q{
INSERT INTO clustermove_inprogress
( userid, locktime, moverhost, moverport, moverinstance )
VALUES
( ?, ?, ?, ?, ? )
};
$ipsth = $dbh->prepare( $sql ) or die "prepare: ", $dbh->errstr;
# Pick a query based on whether the user wants only active users.
if ( $self->activeUsersOnly ) {
$sql = sprintf q{
SELECT
userid
FROM
clustertrack2
WHERE
timeactive > UNIX_TIMESTAMP() - 86400*%d
AND clusterid = ?
LIMIT %d
}, $self->activeDays, $limit;
} else {
$sql = sprintf q{
SELECT
user,
userid,
statusvis,
clusterid
FROM user
WHERE clusterid = ?
LIMIT %d
}, $limit;
}
$iip = unpack( 'N', pack('C4', split( /\./, $self->lockIp )) );
@users = ();
# Fetch users for each cluster
foreach my $cid ( @{$self->{sources}} ) {
# Either get the cluster master handle for active users, or reuse the
# current one for all users
$seldbh = $self->activeUsersOnly ? LJ::get_cluster_master($cid) : $dbh;
die "Couldn't obtain db handle for cluster $cid\n" unless $seldbh;
# Prepare the selection cursor and execute it
$selsth = $seldbh->prepare( $sql ) or die "prepare: ", $seldbh->errstr;
$self->debugMsg( "Running user-select query '%s' on cluster %d", $sql, $cid );
$selsth->execute( $cid ) or die "execute: ", $selsth->errstr;
while (( $row = $selsth->fetchrow_hashref )) {
next if exists $self->{userThreads}{$row->{userid}}
or exists $self->{fakeMovedUsers}{$row->{userid}};
# populate the rest of the row
if ($self->activeUsersOnly) {
my $u = LJ::load_userid($row->{userid}, "force");
die "Couldn't load userid: $row->{userid}" unless $u;
# if for some reason this user had a clustertrack2 row they shouldn't have,
# delete the clustertrack2 on this cluster and move along.
if ($u->{'clusterid'} != $cid) {
$seldbh->do("DELETE FROM clustertrack2 WHERE userid=? AND clusterid=?",
undef, $u->{userid}, $cid);
print("deleted invalid clustertrack2 for userid=$u->{userid} ",
"(not cluster $cid, but $u->{clusterid}\n");
next;
}
$row = $u;
}
# Insert the user in the in-progress table, skipping users who're
# already being moved by another mover
next unless
$ipsth->execute( $row->{userid}, time, $iip,
$self->lockPort, $self->instanceId );
$self->debugMsg( "Selected row: %s", $row );
push @users, {%$row};
} continue {
$self->debugMsg( "DBI error: %s", $DBI::errstr ) if $DBI::errstr;
}
}
$ipsth->finish;
return sort { $a->{userid} <=> $b->{userid} } @users;
}
### METHOD: getMaxThreads()
### Fetch the maximum number of threads from the config file, or return a
### default if the config file doesn't exist or is unreadable.
sub getMaxThreads {
my $self = shift or confess "Cannot be called as a function";
my $maxThreads = shift;
if ( -r $MoverWorkersFile ) {
$self->{moverWorkersMtime} ||= (stat _)[9];
my $mtime = $self->{moverWorkersMtime};
if ( !defined $maxThreads || (stat _)[9] > $mtime ) {
$self->{moverWorkersMtime} = (stat _)[9];
$self->message( "(Re)-reading $MoverWorkersFile:\n\t%s < %s",
scalar localtime($mtime),
scalar localtime($self->{moverWorkersMtime}) );
# Read the process limit from a file, or default to unlimited
if ( open my $ifh, $MoverWorkersFile ) {
chomp( $maxThreads = <$ifh> );
$maxThreads = int($maxThreads);
}
}
}
$maxThreads = 1 if !defined $maxThreads;
return $maxThreads;
}
### METHOD: setSignalHandlers()
### Set up signal handlers to toggle shutdown flags in the object, saving any
### current handlers.
sub setSignalHandlers {
my $self = shift or confess "Cannot be called as a function";
$self->debugMsg( "Installing new signal handlers." );
$self->{_signals}{HUP} = $SIG{HUP};
$SIG{HUP} = sub { $self->{_shutdownFlag} = 1 };
$self->{_signals}{INT} = $SIG{INT};
$SIG{INT} = sub { $self->{_shutdownFlag} = 1 };
$self->{_signals}{TERM} = $SIG{TERM};
$SIG{TERM} = sub { $self->{_haltFlag} = 1 };
return 1;
}
### METHOD: restoreSignalHandlers()
### Restore the signal handlers that were saved by setSignalHandlers().
sub restoreSignalHandlers {
my $self = shift or confess "Cannot be called as a function";
$self->debugMsg( "Restoring initial signal handlers." );
foreach my $signal ( keys %{$self->{_signals}} ) {
$SIG{$signal} = $self->{_signals}{$signal};
}
return 1;
}
### (PROXY) METHOD: AUTOLOAD( @args )
### Proxy method to build object accessors.
sub AUTOLOAD {
my $self = shift or croak "Cannot be called as a function";
( my $name = $AUTOLOAD ) =~ s{.*::}{};
my $method;
if ( ref $self && exists $self->{$name} ) {
# Define an accessor for this attribute
$method = sub : lvalue {
my $closureSelf = shift or croak "Can't be used as a function.";
$closureSelf->{$name} = shift if @_;
return $closureSelf->{$name};
};
# Install the new method in the symbol table
NO_STRICT_REFS: {
no strict 'refs';
*{$AUTOLOAD} = $method;
}
# Now jump to the new method after sticking the self-ref back onto the
# stack
unshift @_, $self;
goto &$AUTOLOAD;
}
# Try to delegate to our parent's version of the method
my $parentMethod = "SUPER::$name";
return $self->$parentMethod( @_ );
}
DESTROY {
my $self = shift;
$self->restoreSignalHandlers;
}
#####################################################################
### M O V E R T H R E A D C L A S S
#####################################################################
package Mover::Thread;
BEGIN {
# LiveJournal functions
require "$ENV{'LJHOME'}/cgi-bin/ljlib.pl";
use vars qw{$AUTOLOAD};
use Carp qw{croak confess};
}
### METHOD: new( $user, $dest )
### Create a mover thread object that will move the specified I<user> to the
### given I<dest> cluster.
sub new {
my $class = shift;
my ( $user, $userid, $src, $dest ) = @_;
# Lock the user
LJ::update_user( $userid, {raw => "caps=caps|(1<<$ReadOnlyBit)"} );
return bless {
userid => $userid,
user => $user,
src => $src,
dest => $dest,
pid => undef,
testingMode => 0,
locked => 1,
}, $class;
}
### METHOD: run()
### Execute the backend mover.
sub run {
my $self = shift or confess "Cannot be called as a function";
# Fork and exec a child, keeping the pid
unless (( $self->{pid} = fork )) {
LJ::disconnect_dbs();
if ( $self->testingMode ) {
my $seconds = int(rand 20) + 3;
printf STDERR "Child %d sleeping %d seconds to simulate move.\n",
$$, $seconds;
sleep $seconds;
} else {
exec( "$ENV{LJHOME}/bin/moveucluster.pl",
"--verbose=0",
"--expungedel",
"--destdel",
"--prelocked",
$self->user,
$self->dest );
}
exit;
}
return $self->pid;
}
### METHOD: unlock()
### Remove the read-only bit from the user this thread corresponds to.
sub unlock {
my $self = shift;
if ( $self->{locked} ) {
print STDERR "Unlocking user $self->{userid}.\n";
LJ::update_user( $self->{userid}, {raw => "caps=caps&~(1<<$ReadOnlyBit)"} );
$self->{locked} = 0;
}
return 1;
}
sub DESTROY {}
### (PROXY) METHOD: AUTOLOAD( @args )
### Proxy method to build object accessors.
sub AUTOLOAD {
my $self = shift or croak "Cannot be called as a function";
( my $name = $AUTOLOAD ) =~ s{.*::}{};
my $method;
if ( ref $self && exists $self->{$name} ) {
# Define an accessor for this attribute
$method = sub : lvalue {
my $closureSelf = shift or croak "Can't be used as a function.";
$closureSelf->{$name} = shift if @_;
return $closureSelf->{$name};
};
# Install the new method in the symbol table
NO_STRICT_REFS: {
no strict 'refs';
*{$AUTOLOAD} = $method;
}
# Now jump to the new method after sticking the self-ref back onto the
# stack
unshift @_, $self;
goto &$AUTOLOAD;
}
# Try to delegate to our parent's version of the method
my $parentMethod = "SUPER::$name";
return $self->$parentMethod( @_ );
}