Justin Clift wrote: > Tom Lane wrote: > > > > Gavin Sherry <[EMAIL PROTECTED]> writes: > > > On Wed, 3 Apr 2002, Christopher Kings-Lynne wrote: > > >> Would it be an idea to have pg_dump append an ANALYZE; command to the end of > > >> its dumps to assist newbies / inexperienced admins? > > > > > I do not think this is desired behaviour. > > > > I agree with Gavin here ... a forced VACUUM or ANALYZE after a restore > > will just get in the way of people who know what they're doing, and it's > > not at all clear that it will help people who do not. > > Sorry Tom and Gavin, but I feel it really comes down to our idea of what > we're > trying to do here : > > a) A database which is very self-maintaining, so people DON'T HAVE to > learn it's intricacies in order to be getting decent performance. > (They'll have to learn the intricacies if they want *better* > performance)
The defaults after a restore should result in index scans most of the time, resulting in some medium decent performance. And PostgreSQL needs some frequent VACUUM anyway, so after a while this problem solves itself for the average user. A database wide forced VACUUM on the other hand can make things worse. I have seen scenarios, where you have to explicitly leave out ANALYZE for specific tables in order to keep them index-scanned. So what you're proposing is to force professional PostgreSQL users to wait after restore for a useless ANALYZE to complete, before they can reset things with a normal VACUUM to get their required performance back? And all that just to make dummies happier? Jan > b) A database which works. But if you want decent performance, you'd > better > take the time and effort to learn it. > (This is the approach the commercial vendors take) > > I feel we should always target a) where it's possible to without it > seriously > getting in the way of people who've take the time to learn the skills. > > The far majority of people who use PostgreSQL are in the category which > will > benefit from a) so they can put their time to other uses instead of > having to > learn and keep-up-to-date-with PostgreSQL. This will *always* be the > case. > > Having decent performance by default should definitely be an important > objective, so having an ANALYZE command run at the end of a restore - by > default only - is a good idea. > > Regards and best wishes, > > Justin Clift > > > regards, tom lane > > > > ---------------------------(end of broadcast)--------------------------- > > TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED] > > -- > "My grandfather once told me that there are two kinds of people: those > who work and those who take the credit. He told me to try to be in the > first group; there was less competition there." > - Indira Gandhi > > ---------------------------(end of broadcast)--------------------------- > TIP 4: Don't 'kill -9' the postmaster > -- #======================================================================# # It's easier to get forgiveness for being wrong than for being right. # # Let's break this rule - forgive me. # #================================================== [EMAIL PROTECTED] # ---------------------------(end of broadcast)--------------------------- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]