Thank you for quick feedback, and I'm sorry for slow response. All of your opinions were very helpful for me.
I have confirmed Greg's Idea "Timing events". http://www.postgresql.org/message-id/509300f7.5000...@2ndquadrant.com Greg said at first, "Parsing log files for commonly needed performance data is no fun." Yes, I completely agree with him. That looks a nice idea but I don't know why this idea has not been commited yet. Anybody knows? I have reworked my idea since I heard dear hacker's opinions. ==================== pg_stat_vacuum view ==================== I understand it is not good to simply add more counters in pg_stat_*_tables. For now, I'd like to suggest an extension which can confirm vacuum statistics like pg_stat_statements. VACUUM is a most important feature in PostgreSQL, but a special view for vacuum does not exist. Don't you think the fact is inconvenience? At least, I am disgruntled with that we need to parse pg_log for tune VACUUM. My first design of pg_stat_vacuum view is following. (There are two views.) pg_stat_vacuum_table --------------- dbid schemaname relid relname elapsed page_removed page_remain page_skipped tuple_removed tuple_remain tuple_notremovable buffer_hit buffer_miss buffer_dirty avg_read avg_write vm_count vac_start vac_end is_autovacuum pg_stat_vacuum_index --------------- dbid shemaname relid indexrelid indexname elapsed num_index_tuples num_pages tuples_removed pages_deleted pages_free is_autovacuum At present, I think memory design of pg_stat_statements can divert into this feature.And I think this module needs to prepare following parameters like pg_stat_statements. pg_stat_vacuum.max(integer) pg_stat_vacuum.save(boolean) pg_stat_vacuum.excluded_dbnames(text) pg_stat_vacuum.excluded_schemas(text) pg_stat_vacuum.min_duration(integer) ... and so on. To implement this feature, I have to collect each vacuum-stats every lazy_vacuum_* and I need to embed a hook function point where needed. (probably last point of lazy_vacuum_rel). Do you hesitate to add the hook only for this function? Similar feature has been already provided by pg_statsinfo package. But it is a full-stack package for PG-stats and it needs to redesign pg_log and design a repository database for introduce. And it is not a core-extension for PostgreSQL. (I don't intend to hate pg_statsinfo, I think this package is a very convinient tool) Everyone will be able to do more easily tuning of VACUUM. That's all I want. Any comments are welcome! Best Regards, Naoya Anzai --- Naoya Anzai Engineering Department NEC Solution Inovetors, Ltd. E-Mail: nao-an...@xc.jp.nec.com --- -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
