Duan Ligong wrote: > Alvaro, Thanks for your answer. > It would be very helpful. > > > > Would you like to be so kind as to answer the following questions: > > > > > > - Is there any way to control the number of clog files and xlog files? > > > I encounter an issue that there are too many clog files under the > > > pg_clog/ directory which occupy more space than I can endure.. > > > > pg_clog files are controlled by tuple freezing, which is done by vacuum, > > and it depends on the autovacuum_min_freeze_age parameter and > > vacuum_freeze_min_age. Please read > > So can we reduce the number of clog by increasing the > autovacuum_min_freeze_age parameter and vacuum_freeze_min_age > ? Yes, but decreasing the value. Sorry, you ask more questions that I have time to answer right now. > I encoutered a scenario that there are many files and some of them > are as old as one month ago. Does all these files including the > old files are still useful for postgresql? and when will they deleted > or rotated? Or should they be deleted and maintained by external > programs? Yes, those files are still useful. They will be deleted eventually. -- Alvaro Herrera http://www.CommandPrompt.com/ PostgreSQL Replication, Consulting, Custom Development, 24x7 support
