我偶尔有一个问题（每周一次或两次，不一定在繁忙时间）查询某个数据库（我的站点中最大的数据库）突然停止响应大约一个小时。 查询开始堆积，主要是“发送数据”和“统计”状态，最终负载大于40，整个服务器停止。
当这个问题发生的时候，如果我禁用这个站点，同一个服务器上的所有其他的站点和dbs运行正常。
我有“显示引擎INNODB状态”的输出，当它没有响应时，我想知道是否有人可以告诉我，如果它显示任何exception – 我已经删除了“交易”部分列出所有挂起的查询，我可以添加如果它会帮助。
5.1.70-cll MySQL社区服务器，没有Innodb插件，CentOS 5.9
提前致谢。
===================================== 130901 17:10:26 INNODB MONITOR OUTPUT ===================================== Per second averages calculated from the last 50 seconds ---------- SEMAPHORES ---------- OS WAIT ARRAY INFO: reservation count 25977, signal count 14540 --Thread 140248378771776 has waited at btr/btr0cur.c line 467 for 1.00 seconds the semaphore: S-lock on RW-latch at 0x7f8e273f8ae8 created in file buf/buf0buf.c line 550 a writer (thread id 140248378771776) has reserved it in mode exclusive number of readers 0, waiters flag 1 Last time read locked in file btr/btr0sea.c line 794 Last time write locked in file buf/buf0buf.c line 1820 --Thread 140248434157888 has waited at btr/btr0cur.c line 467 for 3.00 seconds the semaphore: S-lock on RW-latch at 0x7f8e272877c8 created in file buf/buf0buf.c line 550 a writer (thread id 140248434157888) has reserved it in mode exclusive number of readers 0, waiters flag 1 Last time read locked in file btr/btr0sea.c line 794 Last time write locked in file buf/buf0buf.c line 1820 Mutex spin waits 0, rounds 550914, OS waits 8104 RW-shared spins 34629, OS waits 16634; RW-excl spins 2759, OS waits 586 -------- FILE I/O -------- I/O thread 0 state: waiting for i/o request (insert buffer thread) I/O thread 1 state: waiting for i/o request (log thread) I/O thread 2 state: doing file i/o (read thread) ev set I/O thread 3 state: waiting for i/o request (write thread) Pending normal aio reads: 172, aio writes: 0, ibuf aio reads: 0, log i/o's: 0, sync i/o's: 0 Pending flushes (fsync) log: 0; buffer pool: 0 105909 OS file reads, 8365 OS file writes, 4079 OS fsyncs 1 pending preads, 1 pending pwrites 106.42 reads/s, 19475 avg bytes/read, 9.50 writes/s, 4.68 fsyncs/s ------------------------------------- INSERT BUFFER AND ADAPTIVE HASH INDEX ------------------------------------- Ibuf: size 20, free list len 70, seg size 91, 1099 inserts, 8617 merged recs, 2154 merges Hash table size 1888559, node heap has 2598 buffer(s) 8189.64 hash searches/s, 941.80 non-hash searches/s --- LOG --- Log sequence number 196 2706819157 Log flushed up to 196 2706818752 Last checkpoint at 196 2705105219 0 pending log writes, 0 pending chkp writes 3880 log i/o's done, 4.42 log i/o's/second ---------------------- BUFFER POOL AND MEMORY ---------------------- Total memory allocated 1061750976; in additional pool allocated 1048576 Dictionary memory allocated 1530760 Buffer pool size 58240 Free buffers 0 Database pages 55642 Modified db pages 1543 Pending reads 172 Pending writes: LRU 120, flush list 0, single page 0 Pages read 127164, created 59, written 5866 126.52 reads/s, 0.08 creates/s, 5.82 writes/s Buffer pool hit rate 996 / 1000 -------------- ROW OPERATIONS -------------- 8 queries inside InnoDB, 27 queries in queue 17 read views open inside InnoDB Main thread process no. 2504, id 140248394586432, state: sleeping Number of rows inserted 963, updated 4397, deleted 5, read 43384960 1.56 inserts/s, 4.92 updates/s, 0.00 deletes/s, 17291.99 reads/s ---------------------------- END OF INNODB MONITOR OUTPUT ============================ 通过将innodb缓冲池增加到ram的60％来解决，并重build数据库（export / drop / import）