slave IO_THREAD blocks replication - sql thread
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
MySQL Server |
Unknown
|
Unknown
|
|||
Percona Server moved to https://jira.percona.com/projects/PS |
Invalid
|
Undecided
|
Unassigned | ||
5.1 |
Won't Fix
|
Medium
|
Unassigned | ||
5.5 |
Triaged
|
Medium
|
Unassigned | ||
5.6 |
Invalid
|
Undecided
|
Unassigned |
Bug Description
After snapshot with Xtrabackup, slave was restored with logical lag about 6 hours. Replication started, no error. Than lag (by Seconds_
STOP SLAVE IO_THREAD;
was slave up2date during <1 hod (with Seconds_
Than IO_THREAD was started again and slave now runs about one day without any lag (there is monitoring).
Sumary
with running SLAVE IO_THREAD replication goes to grew lag and not catch master during 1 day.
Withhout running SLAVE IO_THREAD replication catch up master <1 hod.
Something wrong!?
Slave is Xeon E5 with SSD for data and SAS 10k for logs. Master is "only" Xeon 56xx with SAS 15k + SAS 10k. All in RAID 1. Acording to our deployment benchmark is slave faster than master (logicaly).
There wasn't any task on slave, which can slow down replication (as raid check, backup, ...).
Both are Percona-
during lag status was
slave
| 2 | system user | | | Connect | 10583 | Waiting for master to send event | | 0 | 0 | 1 |
| 3 | system user | | | Connect | 35127 | Reading event from the relay log | | 0 | 0 | 1 |
master
| 10174490 | repl_isp_pr | ...:43412 | | Binlog Dump | 10607 | Master has sent all binlog to slave; waiting for binlog to be updated |