scripts/memcached-tool

#!/usr/bin/perl
#
# memcached-tool:
#   stats/management tool for memcached.
#
# Author:
#   Brad Fitzpatrick <brad@danga.com>
#
# Contributor:
#   Andrey Niakhaichyk <andrey@niakhaichyk.org>
#
# License:
#   public domain.  I give up all rights to this
#   tool.  modify and copy at will.
#

use strict;
use IO::Socket::INET;
use URI::Escape;

my $addr = shift;
my $mode = shift || "display";
my ($from, $to);
my $limit;
my $unescape = 0;

if ($mode eq "display") {
    undef $mode if @ARGV;
} elsif ($mode eq "move") {
    $from = shift;
    $to = shift;
    undef $mode if $from < 6 || $from > 17;
    undef $mode if $to   < 6 || $to   > 17;
    print STDERR "ERROR: parameters out of range\n\n" unless $mode;
} elsif ($mode eq 'dump') {
    if (@ARGV) {
        $limit = shift;
        undef $mode if $limit < 1;
        print STDERR "ERROR: invalid limit (should be a positive number)\n\n" unless $mode;
    }
} elsif ($mode eq 'keys') {
    if (@ARGV) {
        my $arg = shift;
        if ($arg eq '-u') {
            $unescape = 1;
        } else {
            $limit = $arg;
        }
        if (@ARGV) {
            $limit = shift;
        }
        if ($limit) {
            undef $mode if $limit < 1;
            print STDERR "ERROR: invalid limit (should be a positive number)\n\n" unless $mode;
        }
    }
} elsif ($mode eq 'stats') {
    ;
} elsif ($mode eq 'settings') {
    ;
} elsif ($mode eq 'sizes') {
    ;
} else {
    undef $mode;
}

undef $mode if @ARGV;

die
    "Usage: memcached-tool <host[:port] | /path/to/socket> [mode]\n
       memcached-tool 10.0.0.5:11211 display           # shows slabs
       memcached-tool 10.0.0.5:11211                   # same.  (default is display)
       memcached-tool 10.0.0.5:11211 stats             # shows general stats
       memcached-tool 10.0.0.5:11211 settings          # shows settings stats
       memcached-tool 10.0.0.5:11211 sizes             # shows sizes stats
       memcached-tool 10.0.0.5:11211 dump [limit]      # dumps keys and values
       memcached-tool 10.0.0.5:11211 keys [-u] [limit] # dumps keys (-u: unescape special characters)

WARNING! sizes is a development command.
As of 1.4 it is still the only command which will lock your memcached instance for some time.
If you have many millions of stored items, it can become unresponsive for several minutes.
Run this at your own risk. It is roadmapped to either make this feature optional
or at least speed it up.
" unless $addr && $mode;


sub server_connect {
    my $sock;
    if ($addr =~ m:/:) {
        $sock = IO::Socket::UNIX->new(
            Peer => $addr,
        );
    }
    else {
        $addr .= ':11211' unless $addr =~ /:\d+$/;

        $sock = IO::Socket::INET->new(
            PeerAddr => $addr,
            Proto    => 'tcp',
        );
    }
    die "Couldn't connect to $addr\n" unless $sock;
    return $sock;
}

my $sock = server_connect();

if ($mode eq 'dump') {
    print STDERR "Dumping memcache contents";
    print STDERR " (limiting to $limit keys)" unless !$limit;
    print STDERR "\n";
    print $sock "lru_crawler metadump all\r\n";
    my %keyexp;
    my $keycount = 0;
    while (<$sock>) {
        last if /^END/ or ($limit and $keycount == $limit);
        # return format looks like this
        # key=foo exp=2147483647 la=1521046038 cas=717111 fetch=no cls=13 size=1232
        if (/^key=(\S+) exp=(-?\d+) .*/) {
            my ($k, $exp) = ($1, $2);
            $k =~ s/%(.{2})/chr hex $1/eg;

            if ($exp == -1) {
                $keyexp{$k} = 0;
            } else {
                $keyexp{$k} = $exp;
            }
        }
        $keycount++;
    }

    if ($limit) {
        # Need to reopen the connection here to stop the metadump in
        # case the key limit was reached.
        #
        # XXX: Once a limit on # of keys returned is introduced in
        # `lru_crawler metadump`, this should be removed and the proper
        # parameter passed in the query above.
        close($sock);
        $sock = server_connect();
    }

    foreach my $k (keys(%keyexp)) {
        print $sock "get $k\r\n";
        my $response = <$sock>;
        if ($response =~ /VALUE (\S+) (\d+) (\d+)/) {
            my $flags = $2;
            my $len = $3;
            my $val;
            read $sock, $val, $len;
            print "add $k $flags $keyexp{$k} $len\r\n$val\r\n";
            # get the END
            $_ = <$sock>;
            $_ = <$sock>;
        }
    }
    exit;
}

if ($mode eq 'keys') {
    print STDERR "Dumping memcache keys";
    print STDERR " (limiting to $limit keys)" unless !$limit;
    print STDERR "\n";
    print $sock "lru_crawler metadump all\r\n";
    my %keyexp;
    my $keycount = 0;
    while (<$sock>) {
        last if /^END/ or ($limit and $keycount == $limit);
        # return format looks like this
        # key=foo exp=2147483647 la=1521046038 cas=717111 fetch=no cls=13 size=1232
        if (/^key=(\S+) exp=(-?\d+) .*/) {
            print ($unescape ? uri_unescape($_) : $_)
        }
        $keycount++;
    }
    exit;
}

if ($mode eq 'stats') {
    my %items;

    print $sock "stats\r\n";

    while (<$sock>) {
        last if /^END/;
        chomp;
        if (/^STAT\s+(\S*)\s+(.*)/) {
            $items{$1} = $2;
        }
    }
    printf ("#%-22s %5s %13s\n", $addr, "Field", "Value");
    foreach my $name (sort(keys(%items))) {
        printf ("%29s %14s\n", $name, $items{$name});

    }
    exit;
}

if ($mode eq 'settings') {
    my %items;

    print $sock "stats settings\r\n";

    while (<$sock>) {
        last if /^END/;
        chomp;
        if (/^STAT\s+(\S*)\s+(.*)/) {
            $items{$1} = $2;
        }
    }
    printf ("#%-17s %5s %11s\n", $addr, "Field", "Value");
    foreach my $name (sort(keys(%items))) {
        printf ("%24s %12s\n", $name, $items{$name});
    }
    exit;
}


if ($mode eq 'sizes') {
    my %items;

    print $sock "stats sizes\r\n";

    while (<$sock>) {
        last if /^END/;
        chomp;
        if (/^STAT\s+(\S*)\s+(.*)/) {
            $items{$1} = $2;
        }
    }
    printf ("#%-17s %5s %11s\n", $addr, "Size", "Count");
    foreach my $name (sort(keys(%items))) {
        printf ("%24s %12s\n", $name, $items{$name});
    }
    exit;
}

# display mode:

my %items;  # class -> { number, age, chunk_size, chunks_per_page,
#            total_pages, total_chunks, used_chunks,
#            free_chunks, free_chunks_end }

print $sock "stats items\r\n";
my $max = 0;
while (<$sock>) {
    last if /^END/;
    if (/^STAT items:(\d+):(\w+) (\d+)/) {
        $items{$1}{$2} = $3;
    }
}

print $sock "stats slabs\r\n";
while (<$sock>) {
    last if /^END/;
    if (/^STAT (\d+):(\w+) (\d+)/) {
        $items{$1}{$2} = $3;
        $max = $1;
    }
}

print "  #  Item_Size  Max_age   Pages   Count   Full?  Evicted Evict_Time OOM\n";
foreach my $n (1..$max) {
    my $it = $items{$n};
    next if (0 == $it->{total_pages});
    my $size = $it->{chunk_size} < 1024 ?
        "$it->{chunk_size}B" :
        sprintf("%.1fK", $it->{chunk_size} / 1024.0);
    my $full = $it->{used_chunks} == $it->{total_chunks} ? "yes" : " no";
    printf("%3d %8s %9ds %7d %7d %7s %8d %8d %4d\n",
           $n, $size, $it->{age}, $it->{total_pages},
           $it->{number}, $full, $it->{evicted},
           $it->{evicted_time}, $it->{outofmemory});
}