I load backup to mariadb and break it. In processlist still present one killed thread:
{code}
show processlist;
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{code}
In same time I run strace for mysqld and see many calls to madvise:
{code}

1. strace -ff -p 33080
   ...
   [pid 60412] madvise(0x7f36cb638000, 331776, MADV_DONTNEED) = 0
   [pid 60412] madvise(0x7f36cb441000, 135168, MADV_DONTNEED) = 0
   [pid 60412] madvise(0x7f36cb638000, 335872, MADV_DONTNEED) = 0
   [pid 60412] madvise(0x7f36cb441000, 135168, MADV_DONTNEED) = 0
   [pid 60412] madvise(0x7f36cb638000, 335872, MADV_DONTNEED) = 0
   [pid 60412] madvise(0x7f36cb441000, 135168, MADV_DONTNEED) = 0
   [pid 60412] madvise(0x7f36cb638000, 335872, MADV_DONTNEED) = 0
   {code}

Table which been loading:
{code}
/*!40101 SET @saved_cs_client = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `contact` (
`id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`id_phonebook` int(10) unsigned NOT NULL DEFAULT '0',
`id_user` int(10) unsigned NOT NULL DEFAULT '0',
`firstname` varchar(255) NOT NULL DEFAULT '',
`lastname` varchar(255) NOT NULL DEFAULT '',
`local_key` varchar(255) NOT NULL DEFAULT '',
PRIMARY KEY (`id`),
KEY `id_phonebook` (`id_phonebook`) USING BTREE,
KEY `id_user` (`id_user`) USING BTREE
) ENGINE=InnoDB AUTO_INCREMENT=133028725 DEFAULT CHARSET=utf8 ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=2;
/*!40101 SET character_set_client = @saved_cs_client */;
{code}