fawzib fawzib - 7 months ago 13
Perl Question

Autokill select MySQL queries perl script

I use the below perl script to kill all select connections done by users but i want to make an exception for the root user since root queries are either important or backup purposes.

Below is my code

#!/usr/bin/perl -w

use DBI;
use strict;

$| = 1;

#------------------------------------------------------------------------------
# !!! Configure check time and timeout. These are both in seconds.

my $check = 15; # check processes every $check seconds
my $slow_time = 60; # stop processes that run for >= $slow_time seconds

# !!! Configure log file - All slow queries also get logged to this file

my $logfile = "./check_mysql_query.log"; # log slow queries to this file

# !!! Configure the database connection parameters

my $db_string = "dbi:mysql:mysql"; # DBI resource to connect to
my $db_user = "root"; # DBI username to connect as
my $db_pass = "password"; # DBI password to connect with

# !!! Configure path to sendmail program

my $sendmail_bin = "/usr/sbin/sendmail";

#
#------------------------------------------------------------------------------


my ($dbh,$sth,$sth2,$thread,$state,$time,$query,$explain);

print "connecting\n";
my $opt = {
'RaiseError'=>0,
'PrintError'=>0
};
$dbh = DBI->connect($db_string,$db_user,$db_pass,$opt);
unless ($dbh) {
print "Error: Unable to connect to database: $DBI::errstr\n";
exit 1;
}

$SIG{'TERM'} = sub {
print "caught sig TERM!\nexiting!\n";
$dbh->disconnect;
exit 1;
};

print "preparing\n";
unless ($sth = $dbh->prepare("show full processlist")) {
print "error preparing query: $DBI::errstr\nexiting!\n";
$dbh->disconnect;
exit 1;
}

print "initialized.. starting loop\n";
while(1) {
unless ($sth->execute) {
print "statement execute failed: ".$sth->errstr."\nexiting!\n";
last;
}
while(my @tmp = $sth->fetchrow) {
$thread = $tmp[0];
$state = $tmp[4];
$time = $tmp[5];
$query = $tmp[7];
if ($state eq "Query" && $query =~ /^SELECT/ && $time >= $slow_time) {
print "killing slow query thread=$thread state=$state time=$time\n";
$dbh->do("kill $thread");
unless (log_query($logfile,$query)) {
print "log_query failed! exiting!\n";
last;
}


}
}
sleep($check);
}

$sth->finish;
$dbh->disconnect;

exit 1;


sub log_query {
my ($file,$query) = @_;
unless (open(O,">>".$file)) {
print "error opening log file '$file': $!\n";
return undef;
}
print O $query."\n-----\n";
close(O);
return 1;
}


script credit: http://code.google.com/p/mysql-killquery/
i removed most of the script code for simplicity.

Answer

I think I get from my reading that your second column will be the user. So assuming root logs into the database as user 'root', then you can probably do this:

while(my @tmp = $sth->fetchrow) {
    next if $tmp[1] eq 'root';
    ...
}