long startup time with many tables, performance_schema=On and open_files_limit > 65534
Affects | Status | Importance | Assigned to | Milestone | ||
---|---|---|---|---|---|---|
Percona Server moved to https://jira.percona.com/projects/PS | Status tracked in 5.7 | |||||
5.5 |
New
|
Undecided
|
Vlad Lesin | |||
5.6 |
New
|
Medium
|
Vlad Lesin | |||
5.7 |
New
|
Medium
|
Vlad Lesin |
Bug Description
We have a Percona Cluster 5.6.16 server with approximately 10,000 databases and a total of approximately 1.5 million tables (~150 tables per Database) as part of our multi-tenant database infrastructure (one database per customer).
When we have performance_
General startup time with our dataset is approximately 2-5 Minutes as all of the tables are read (in a single threaded process).
Crash recovery takes on average approximately 20-30 Minutes on our hardware (again, this is a single-threaded process to load all the tables).
When performance_
All of our databases are named with sequential numbers and using lsof we could see which tables were being opened. The process appeared to be getting much slower as it progressed through the tables on disk.
With performance_
Please let me know what information you would like me to provide.
Thank you for the problem report. I suspect this is a problem inherited from upstream MySQL 5.6.x.
Please, send your my.cnf file content and the output of:
show engine performance_schema status;
when performance_schema is ON. How many tables do you have on this instance, in all databases in total?