#!/usr/bin/perl

use strict;

use warnings;

use Test::More tests => 130;

use FindBin qw($Bin);

use lib "$Bin/lib";

use MemcachedTest;

# Enable manual slab reassign, cap at 6 slabs

my $server = new_memcached('-o slab_reassign -m 4');

my $stats = mem_stats($server->sock, ' settings');

is($stats->{slab_reassign}, "yes");

my $sock = $server->sock;

# Fill a largeish slab until it evicts (honors the -m 6)

my $bigdata = 'x' x 70000; # slab 31

for (1 .. 60) {

    print $sock "set bfoo$_ 0 0 70000\r\n", $bigdata, "\r\n";

    is(scalar <$sock>, "STORED\r\n", "stored key");

}

# Fill a smaller slab until it evicts

my $smalldata = 'y' x 20000; # slab 25

for (1 .. 60) {

    print $sock "set sfoo$_ 0 0 20000\r\n", $smalldata, "\r\n";

    is(scalar <$sock>, "STORED\r\n", "stored key");

}

my $items_before = mem_stats($sock, "items");

isnt($items_before->{"items:31:evicted"}, 0, "slab 31 evicted is nonzero");

isnt($items_before->{"items:25:evicted"}, 0, "slab 25 evicted is nonzero");

my $slabs_before = mem_stats($sock, "slabs");

# Move a large slab to the smaller slab

print $sock "slabs reassign 31 25\r\n";

is(scalar <$sock>, "OK\r\n", "slab rebalancer started");

# Still working out how/if to signal the thread. For now, just sleep.

sleep 2;

# Check that stats counters increased

my $slabs_after = mem_stats($sock, "slabs");

$stats = mem_stats($sock);

isnt($stats->{slabs_moved}, 0, "slabs moved is nonzero");

# Check that slab stats reflect the change

ok($slabs_before->{"31:total_pages"} != $slabs_after->{"31:total_pages"},

    "slab 31 pagecount changed");

ok($slabs_before->{"25:total_pages"} != $slabs_after->{"25:total_pages"},

    "slab 25 pagecount changed");

# Try to move another slab, see that you can move two in a row

print $sock "slabs reassign 31 25\r\n";

like(scalar <$sock>, qr/^OK/, "Cannot re-run against class with empty space");

# Try to move a page backwards. Should complain that source class isn't "safe"

# to move from.

# TODO: Wait until the above command completes, then try to move it back?

# Seems pointless...

#print $sock "slabs reassign 25 31\r\n";

#like(scalar <$sock>, qr/^UNSAFE/, "Cannot move an unsafe slab back");

# Try to insert items into both slabs

print $sock "set bfoo51 0 0 70000\r\n", $bigdata, "\r\n";

is(scalar <$sock>, "STORED\r\n", "stored key");

print $sock "set sfoo51 0 0 20000\r\n", $smalldata, "\r\n";

is(scalar <$sock>, "STORED\r\n", "stored key");

# Do need to come up with better automated tests for this.