We are using MySQL5.1 (5.1.49-3) on debian squeeze and have it setup in a Master/Slave
relationship. The master is a VM on our primary XenServer and the slave is a VM on our
secondary XenServer. The VMs are not using SWAP. The VMs have the following resources:
Master: 4 x VCPUs, 10GB of Memory, 8GB System Disk, 100GB Data Disk (for mysql, disk on
iSCSI NAS)
Slave: 1 x VCPUs, 6GB of Memory, 8GB System Disk, 100GB Data Disk (for mysql, disk on
local server storage)
Each night at 12:30am we run a mysqldump backup from the slave using the following
process. This process takes about 45 mins to complete.
1). Stop Slave
2). Mysqldump each database (/usr/bin/mysqldump -u ********* -p'*********' -h SLAVE_HOST
--routines --databases $db | /bin/gzip -9 > /path/to/backup/MySQL5Dump-$db-$NOW.gz)
3). Start Slave
The problem we have is that the slave is taking ages to catch up. Im pretty sure that at
that time in the morning the transactions are minimal... For example, i had to stop last
nights backup as the slave had not caught up, and has still not caught up nearly 24 hours
later. I weird thing is it seems like it has been taking longer and longer to catch over
the last month or so...
Any ideas?
Thanks
Simon