Re: [PERFORM] extremly low memory usage

2005-08-21 Thread Marko Ristola
I'm Sorry, that I wrote that the option would risk the LOG persistency with PostgreSQL. I should have asked instead, that how you have taken this into account. Tom Lane's email below convinces me, that you have taken the metadata only journalling into account and still fulfill the persistency of

Re: [PERFORM] extremly low memory usage

2005-08-21 Thread Jeremiah Jahn
On Sat, 2005-08-20 at 21:32 -0500, John A Meinel wrote: > Ron wrote: > > At 02:53 PM 8/20/2005, Jeremiah Jahn wrote: > > > >> On Fri, 2005-08-19 at 16:03 -0500, John A Meinel wrote: > >> > Jeremiah Jahn wrote: > >> > > On Fri, 2005-08-19 at 12:18 -0500, John A Meinel wrote: > >> > > > >> > >> > >

Re: [PERFORM] extremly low memory usage

2005-08-21 Thread John A Meinel
Jeremiah Jahn wrote: On Sat, 2005-08-20 at 21:32 -0500, John A Meinel wrote: Ron wrote: At 02:53 PM 8/20/2005, Jeremiah Jahn wrote: Well, since you can get a read of the RAID at 150MB/s, that means that it is actual I/O speed. It may not be cached in RAM. Perhaps you could try the same te

[PERFORM] (Re)-indexing on updates

2005-08-21 Thread Yves Vindevogel
Hi, Say I have a table with column A, B, C, D A has a unique index on it (primary key) B and C have a normal index on it D has no index If I perform a query likeupdate tbl set D = 'whatever' ; that should make no difference on the indexes on the other columns, right ? Or is there some kind o

Fwd: [PERFORM] (Re)-indexing on updates

2005-08-21 Thread Yves Vindevogel
I always forget that this goes to the writer itself and not to the group. Ok, this is a major setback in some of my procedures. From time to time, I must update one field in about 10% of the records. So this will take time. How can I work around that ? Some personal opinions ... 1) Drop indexes

Re: [PERFORM] (Re)-indexing on updates

2005-08-21 Thread Jeffrey W. Baker
On Sun, 2005-08-21 at 20:32 +0200, Yves Vindevogel wrote: > > > __ > > Hi, > > Say I have a table with column A, B, C, D > A has a unique index on it (primary key) > B and C have a normal index on it > D has no index > > If I

Re: [PERFORM] extremly low memory usage

2005-08-21 Thread Ron
I'm resending this as it appears not to have made it to the list. At 10:54 AM 8/21/2005, Jeremiah Jahn wrote: On Sat, 2005-08-20 at 21:32 -0500, John A Meinel wrote: > Ron wrote: > > Well, since you can get a read of the RAID at 150MB/s, that means that > it is actual I/O speed. It may not be ca

Re: [PERFORM] extremly low memory usage

2005-08-21 Thread Ron
At 10:54 AM 8/21/2005, Jeremiah Jahn wrote: On Sat, 2005-08-20 at 21:32 -0500, John A Meinel wrote: > Ron wrote: > > Well, since you can get a read of the RAID at 150MB/s, that means that > it is actual I/O speed. It may not be cached in RAM. Perhaps you could > try the same test, only using say