mysql：设置innodb_force_recovery 导致无限loop

当数据库设置innodb_force_recovery 参数并且重启的时候，

alter日志里面会打出无限多的Waiting for the background threads to start

那是因为 设置innodb_force_recovery 导致无限loop

原因：

mysql 原代码的脚本：

innodb_purge_thread 默认值是1

while (srv_shutdown_state == SRV_SHUTDOWN_NONE) {

if (srv_thread_has_reserved_slot(SRV_MASTER) == ULINT_UNDEFINED

|| (srv_n_purge_threads == 1

&& srv_thread_has_reserved_slot(SRV_WORKER)

== ULINT_UNDEFINED)) {

ut_print_timestamp(stderr);

fprintf(stderr, " InnoDB: "

"Waiting for the background threads to "

"start\n");

os_thread_sleep(1000000);

} else {

break;

}

}





解决的办法是 ：

在设置 innodb_force_recovery >2 的同时

也要加上：

innodb_purge_thread = 0





InnoDB: 1 transaction(s) which must be rolled back or cleaned up

InnoDB: in total 27581870 row operations to undo

InnoDB: Trx id counter is 14F00

130507 14:13:12 InnoDB: Starting an apply batch of log records to the database...

InnoDB: Progress in percents: 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55

56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99

InnoDB: Apply batch completed

InnoDB: Last MySQL binlog file position 0 479663790, file name /opt/mysql/log/mysql-bin.000392

130507 14:13:17 InnoDB: Waiting for the background threads to start

130507 14:13:18 InnoDB: Waiting for the background threads to start

130507 14:13:19 InnoDB: Waiting for the background threads to start

130507 14:13:20 InnoDB: Waiting for the background threads to start

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