do a show full processlist on the 4th slave and see what process is running. This will the sql's running which will be the cause of the slowness.
Also u need to check on the INTERNET bandwidth from the current data center to the other data center. On 6/18/08, Sagar, Sanjeev <[EMAIL PROTECTED]> wrote: > > Hello All, > > > > I've 4 slaves of a master. Out of 4, 3 are in same data center and have > no issues. The fourth one is in another data center and some time that > slave sql_thread lag behind more then 5000 sec. It's only sql_thread, > which slow down. All H/W, S/W and my.cnf files are same for all slaves. > > > > I ran the mysqladmin extended-status in iterative mode and following > kind of results are there in my log file > > > > | Variable_name | Value | > > +----------------------------+-----------+ > > | Bytes_received | 2117975 | > > | Com_insert | 39 | > > | Com_show_slave_status | 4 | > > | Com_show_status | 1 | > > | Com_update | 49 | > > | Connections | 1 | > > | Handler_read_key | 49 | > > | Handler_read_next | 2 | > > | Handler_update | 3629 | > > | Key_blocks_not_flushed | 1 | > > | Key_blocks_unused | -21 | > > | Key_blocks_used | 21 | > > | Key_reads | 21 | > > | Key_write_requests | 94 | > > | Key_writes | 75 | > > | Max_used_connections | 1 | > > | Questions | 93 | > > | Table_locks_immediate | 88 | > > | Threads_connected | 1 | > > | Threads_created | 1 | > > +----------------------------+-----------+ > > > > +----------------------------+-----------+ > > | Variable_name | Value | > > +----------------------------+-----------+ > > | Bytes_received | 1469626 | > > | Bytes_sent | 3837 | > > | Com_delete | 2 | > > | Com_insert | 143 | > > | Com_show_status | 1 | > > | Com_update | 1247 | > > | Handler_delete | 5 | > > | Handler_read_key | 1249 | > > | Handler_read_next | 73 | > > | Handler_read_rnd | 8379 | > > | Handler_update | 9625 | > > | Handler_write | 8492 | > > | Key_blocks_not_flushed | 1 | > > | Key_blocks_unused | -158 | > > | Key_blocks_used | 158 | > > | Key_read_requests | 52672 | > > | Key_reads | 158 | > > | Questions | 1394 | > > | Table_locks_immediate | 1392 | > > | Threads_cached | 1 | > > | Threads_connected | -1 | > > > > > > > > > > Any idea any one, that what can be tunned here for keeping sql_thread > running same as other slaves. My key_buffers are set to 1G in cnf file. > Also on this slave, no binary logging is enabled or no slow log is > enabled. And no application is connected. This is purely stand alone > slave for disaster recovery. > > > > Regards, > > > > > >
