On Fri, 29 Apr 2005, Christopher Browne wrote:
Martha Stewart called it a Good Thing when [EMAIL PROTECTED] ("Marc G. Fournier") wrote:I know one person was talking about being able to target only those that pages that have changes, instead of the whole table ... but some sort of "load monitoring" that checks # of active connections and tries to find 'lulls'?
I have some "log table purging" processes I'd like to put in place; it would be really slick to be able to get some statistics from the system as to how busy the DB has been in the last little while.
The nice, adaptive algorithm:
- Loop forever
- Once a minute, evaluate how busy things seem, giving some metric X
-> If X is "high" then purge 10 elderly tuples from table log_table -> If X is "moderate" then purge 100 elderly tuples from table log_table -> If X is "low" then purge 1000 elderly tuples from table log_table
The trouble is in measuring some form of "X."
Some reasonable approximations might include: - How much disk I/O was recorded in the last 60 seconds? - How many application transactions (e.g. - invoices or such) were issued in the last 60 seconds (monitoring a sequence could be good enough).
Some way of doing a 'partial vacuum' would be nice ... where a VACUUM could stop after it processed those '10 elderly tuples' and on the next pass, resume from that point instead of starting from the beginning again ...
---- Marc G. Fournier Hub.Org Networking Services (http://www.hub.org) Email: [EMAIL PROTECTED] Yahoo!: yscrappy ICQ: 7615664
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