Fehler beim Abrufen des abgelaufenen Objekts aus Memcached

Question

Ich versuche zu lernen, wie Sie das Memcached-Plugin in MySQL 5.6 verwenden. Ich benutzte telnet, um Werte zu memcached zu erhalten und zu setzen. Wenn ich versuche, einen abgelaufenen Wert aus Memcache zu erhalten, heißt es "Verbindung geschlossen durch fremden Host.". Weitere Details sind unten:

Datenbankname: Test

Tabellenname: Demo

meine Tabellenbeschreibung

+-------+---------------------+------+-----+---------+-------+ 
| Field | Type    | Null | Key | Default | Extra | 
+-------+---------------------+------+-----+---------+-------+ 
| c1 | varchar(32)   | NO | PRI | NULL |  | 
| c21 | varchar(1024)  | YES |  | NULL |  | 
| c22 | varchar(1024)  | YES |  | NULL |  | 
| c3 | int(11)    | YES |  | NULL |  | 
| c4 | bigint(20) unsigned | YES |  | NULL |  | 
| c5 | int(11)    | YES |  | NULL |  | 
+-------+---------------------+------+-----+---------+-------+ 

meine Tabelleninhalte

+----+------+------+------+------+------------+ 
| c1 | c21 | c22 | c3 | c4 | c5   | 
+----+------+------+------+------+------------+ 
| a | aaaa | aaaa | 0 | 1 |   0 | 
| b | aa | aa | 0 | 2 | 1390372227 | 
+----+------+------+------+------+------------+ 

Container Tisch

+------+-----------+-----------+-------------+---------------+-------+------------+--------------------+------------------------+ 
| name | db_schema | db_table | key_columns | value_columns | flags | cas_column | expire_time_column | unique_idx_name_on_key | 
+------+-----------+-----------+-------------+---------------+-------+------------+--------------------+------------------------+ 
| aaa | test  | demo_test | c1   | c2   | c3 | c4   | c5     | PRIMARY    | 
| bb | test  | demo  | c1   | c21,c22  | c3 | c4   | c5     | PRIMARY    | 
+------+-----------+-----------+-------------+---------------+-------+------------+--------------------+------------------------+ 

Cache-Regeln Tabelle

+--------------+-------------+-------------+---------------+--------------+ 
| policy_name | get_policy | set_policy | delete_policy | flush_policy | 
+--------------+-------------+-------------+---------------+--------------+ 
| cache_policy | innodb_only | innodb_only | innodb_only | innodb_only | 
+--------------+-------------+-------------+---------------+--------------+ 

Telnet-Verbindung

~ ⮀ telnet localhost 11211 
Trying 127.0.0.1... 
Connected to localhost. 
Escape character is '^]'. 
get @@bb 
VALUE @@bb 0 9 
test/demo 
END 
get a 
VALUE a 0 9 
aaaa|aaaa 
END 
get c 
END 
get d 
END 
get b 
Connection closed by foreign host. 

Es gibt kein Problem, wenn ich versuche, einen Wert nicht in Memcached zu bekommen, oder wenn ich versuche, Erhalten Sie einen Wert, der nicht abgelaufen ist. Dies geschieht auch nur bei Tabellen mit mehreren Wertespalten (hier c21 und c22). Wenn ich dasselbe für eine Tabelle mit nur einer Wertespalte tue, gibt es kein Problem.

Und nachdem die Verbindung geschlossen ist, wenn ich versuche, die Datenbank abzufragen, wird die folgenden Fehler angezeigt:

mysql> select * from innodb_memcache.cache_policies; 
ERROR 2006 (HY000): MySQL server has gone away 
No connection. Trying to reconnect... 
Connection id: 1 
Current database: test 

Und manchmal zeigt es die folgende Fehlermeldung:

*** glibc detected *** /opt/mysql/server-5.6/bin/mysqld: free(): invalid pointer: 0x00007f053c008827 *** 
======= Backtrace: ========= 
/lib/x86_64-linux-gnu/libc.so.6(+0x7eb96)[0x7f0596f39b96] 
/opt/mysql/server-5.6/lib/plugin//innodb_engine.so(+0xb170)[0x7f0547df3170] 
/opt/mysql/server-5.6/lib/plugin/libmemcached.so(+0x10bbb)[0x7f0569475bbb] 
/opt/mysql/server-5.6/lib/plugin/libmemcached.so(+0x157b0)[0x7f056947a7b0] 
/opt/mysql/server-5.6/lib/plugin/libmemcached.so(+0x16cec)[0x7f056947bcec] 
/opt/mysql/server-5.6/lib/plugin/libmemcached.so(conn_parse_cmd+0x11)[0x7f056947c931] 
/opt/mysql/server-5.6/lib/plugin/libmemcached.so(+0x9bdc)[0x7f056946ebdc] 
/opt/mysql/server-5.6/lib/plugin/libmemcached.so(event_base_loop+0x286)[0x7f05694810d6] 
/opt/mysql/server-5.6/lib/plugin/libmemcached.so(+0x19bb2)[0x7f056947ebb2] 
/lib/x86_64-linux-gnu/libpthread.so.0(+0x7e9a)[0x7f05982dbe9a] 
/lib/x86_64-linux-gnu/libc.so.6(clone+0x6d)[0x7f0596faf3fd] 
======= Memory map: ======== 
00400000-00f6f000 r-xp 00000000 08:03 21495897       /opt/mysql/server-5.6/bin/mysqld 
0116f000-0131a000 rw-p 00b6f000 08:03 21495897       /opt/mysql/server-5.6/bin/mysqld 
0131a000-0136d000 rw-p 00000000 00:00 0 
01a44000-021a0000 rw-p 00000000 00:00 0         [heap] 
7f0534000000-7f0534021000 rw-p 00000000 00:00 0 
7f0534021000-7f0538000000 ---p 00000000 00:00 0 
7f053c000000-7f053c021000 rw-p 00000000 00:00 0 
7f053c021000-7f0540000000 ---p 00000000 00:00 0 
7f0540000000-7f05402dd000 rw-p 00000000 00:00 0 
7f05402dd000-7f0544000000 ---p 00000000 00:00 0 
7f05445e1000-7f05445e2000 ---p 00000000 00:00 0 
7f05445e2000-7f0544de2000 rw-p 00000000 00:00 0       [stack:30166] 
7f0544de2000-7f0544de3000 ---p 00000000 00:00 0 
7f0544de3000-7f05455e3000 rw-p 00000000 00:00 0       [stack:30160] 
7f05455e3000-7f05455e4000 ---p 00000000 00:00 0 
7f05455e4000-7f0545de4000 rw-p 00000000 00:00 0       [stack:30161] 
7f0545de4000-7f0545de5000 ---p 00000000 00:00 0 
7f0545de5000-7f05465e5000 rw-p 00000000 00:00 0       [stack:30162] 
7f05465e5000-7f05465e6000 ---p 00000000 00:00 0 
7f05465e6000-7f0546de6000 rw-p 00000000 00:00 0       [stack:30163] 
7f0546de6000-7f0546de7000 ---p 00000000 00:00 0 
7f0546de7000-7f05475e7000 rw-p 00000000 00:00 0       [stack:30165] 
7f05475e7000-7f05475e8000 ---p 00000000 00:00 0 
7f05475e8000-7f0547de8000 rw-p 00000000 00:00 0       [stack:30164] 
7f0547de8000-7f0547e00000 r-xp 00000000 08:03 21505464     /opt/mysql/server-5.6/lib/plugin/innodb_engine.so 
7f0547e00000-7f0547fff000 ---p 00018000 08:03 21505464     /opt/mysql/server-5.6/lib/plugin/innodb_engine.so 
7f0547fff000-7f0548000000 rw-p 00017000 08:03 21505464     /opt/mysql/server-5.6/lib/plugin/innodb_engine.so 
7f0548000000-7f0548022000 rw-p 00000000 00:00 0 
7f0548022000-7f054c000000 ---p 00000000 00:00 0 
7f054c000000-7f054c021000 rw-p 00000000 00:00 0 
7f054c021000-7f0550000000 ---p 00000000 00:00 0 
7f0550000000-7f0550021000 rw-p 00000000 00:00 0 
7f0550021000-7f0554000000 ---p 00000000 00:00 0 
7f0554000000-7f0554021000 rw-p 00000000 00:00 0 
7f0554021000-7f0558000000 ---p 00000000 00:00 0 
7f0558000000-7f0558021000 rw-p 00000000 00:00 0 
7f0558021000-7f055c000000 ---p 00000000 00:00 0 
7f055c000000-7f055c07a000 rw-p 00000000 00:00 0 
7f055c07a000-7f0560000000 ---p 00000000 00:00 0 
7f0560000000-7f0560021000 rw-p 00000000 00:00 0 
7f0560021000-7f0564000000 ---p 00000000 00:00 0 
7f0564041000-7f0564042000 ---p 00000000 00:00 0 
7f0564042000-7f0564842000 rw-p 00000000 00:00 0 
7f0564842000-7f0564843000 ---p 00000000 00:00 0 
7f0564843000-7f0565043000 rw-p 00000000 00:00 0       [stack:19202] 
7f0565043000-7f0565044000 ---p 00000000 00:00 0 
7f0565044000-7f0565844000 rw-p 00000000 00:00 0       [stack:19201] 
7f0565844000-7f0565845000 ---p 00000000 00:00 0 
7f0565845000-7f0566045000 rw-p 00000000 00:00 0       [stack:19200] 
7f0566045000-7f0566046000 ---p 00000000 00:00 0 
7f0566046000-7f0566846000 rw-p 00000000 00:00 0       [stack:19199] 
7f0566846000-7f0566847000 ---p 00000000 00:00 0 
7f0566847000-7f0567047000 rw-p 00000000 00:00 0       [stack:19198] 
7f0567047000-7f0567048000 ---p 00000000 00:00 0 
7f0567048000-7f0567848000 rw-p 00000000 00:00 0       [stack:19197] 
7f0567848000-7f0567849000 ---p 00000000 00:00 0 
7f0567849000-7f0568049000 rw-p 00000000 00:00 0       [stack:19196] 
7f0568049000-7f056804a000 ---p 00000000 00:00 0 
7f056804a000-7f056884a000 rw-p 00000000 00:00 0       [stack:19195] 
7f056884a000-7f056884b000 ---p 00000000 00:00 0 
7f056884b000-7f05692d8000 rw-p 00000000 00:00 0       [stack:19194] 
7f0569465000-7f056948f000 r-xp 00000000 08:03 21505461     /opt/mysql/server-5.6/lib/plugin/libmemcached.so 
7f056948f000-7f056968f000 ---p 0002a000 08:03 21505461     /opt/mysql/server-5.6/lib/plugin/libmemcached.so 
7f056968f000-7f0569691000 rw-p 0002a000 08:03 21505461     /opt/mysql/server-5.6/lib/plugin/libmemcached.so 
7f0569691000-7f0569694000 rw-p 00000000 00:00 0 
7f0569694000-7f0569695000 ---p 00000000 00:00 0 
7f0569695000-7f05696c5000 rw-p 00000000 00:00 0       [stack:20139] 
7f05696c5000-7f05696c6000 ---p 00000000 00:00 0 
7f05696c6000-7f05696f6000 rw-p 00000000 00:00 0       [stack:19203] 
7f05696f6000-7f05696f7000 ---p 00000000 00:00 0 
7f05696f7000-7f0569ef7000 rw-p 00000000 00:00 0       [stack:19192] 
7f0569ef7000-7f0569ef8000 ---p 00000000 00:00 0 
7f0569ef8000-7f056a6f8000 rw-p 00000000 00:00 0       [stack:19191] 
7f056a6f8000-7f056a6f9000 ---p 00000000 00:00 0 
7f056a6f9000-7f056aef9000 rw-p 00000000 00:00 0       [stack:19190] 
7f056aef9000-7f056aefa000 ---p 00000000 00:00 0 
7f056aefa000-7f056b6fa000 rw-p 00000000 00:00 0       [stack:19189] 
7f056b6fa000-7f056b6fb000 ---p 00000000 00:00 0 
7f056b6fb000-7f056befb000 rw-p 00000000 00:00 0       [stack:19188] 
7f056befb000-7f056befc000 ---p 00000000 00:00 0 
7f056befc000-7f056c6fc000 rw-p 00000000 00:00 0       [stack:19187] 
7f056c6fc000-7f056c6fd000 ---p 00000000 00:00 0 
7f056c6fd000-7f056cefd000 rw-p 00000000 00:00 0       [stack:19186] 
7f056cefd000-7f056cefe000 ---p 00000000 00:00 0 
7f056cefe000-7f056d6fe000 rw-p 00000000 00:00 0       [stack:19185] 

Answer 1

Dies ist ein Fehler, Ihre Verbindung wird wegen des Server-Crash-Protokolls, das Sie gepostet haben, geschlossen.

Dieses Problem ist bekannt und wird hoffentlich in einer zukünftigen Version behoben, in der Zwischenzeit könnten Sie die Verwendung des Tabellenpräfixes (@@ bb) vermeiden, da dies der Schlüssel zum Problem ist.