To Fragment or Not to Fragment?
Hi Guys/Gals, IDS 11.50.FC5 O/S AIX 5.3 I am working on one of my inherited instances and I am wondering when fragmentation becomes advantageous. More specifically, I have a table with approx. 300,000 rows. Would fragmentation (by expression) help me on this or is it just too small to make much of a difference. This of course assumes that my fragmentation scheme and my where clauses all look like they should. I know that there is not an exact answer but does anyone have any practical rule of thumb numbers? thanx, Dan
On 12/07/2011 17:31, DAN MUELLER wrote: > Hi Guys/Gals, > > IDS 11.50.FC5 > O/S AIX 5.3 > > I am working on one of my inherited instances and I am wondering when > fragmentation becomes advantageous. More specifically, I have a table with > approx. 300,000 rows. Would fragmentation (by expression) help me on this or > is it just too small to make much of a difference. This of course assumes that > my fragmentation scheme and my where clauses all look like they should. > > I know that there is not an exact answer but does anyone have any practical > rule of thumb numbers? 1M rows: at least own dbspace 10M rows: consider fragmenting 100M rows: must fragment I generally aim to have no more than 50M rows per fragment. I really wouldn't pay any attention to a 300K row table unless it was unusually "hot". -- Cheers, Obnoxio The Clown http://obotheclown.blogspot.com I will now proceed to pleasure myself with this fish.
The exception would be a table that's going to get tons of inserts from multiple users, then I might fragment round robin even for an initially small table to spread the load and reduce contention. Art Art S. Kagel Advanced DataTools (www.advancedatatools.com) Blog: http://informix-myview.blogspot.com/ Disclaimer: Please keep in mind that my own opinions are my own opinions and do not reflect on my employer, Advanced DataTools, the IIUG, nor any other organization with which I am associated either explicitly, implicitly, or by inference. Neither do those opinions reflect those of other individuals affiliated with any entity with which I am affiliated nor those of the entities themselves. On Tue, Jul 12, 2011 at 12:52 PM, Obnoxio The Clown <obnoxio@serendipita.com > wrote: > On 12/07/2011 17:31, DAN MUELLER wrote: > > Hi Guys/Gals, > > > > IDS 11.50.FC5 > > O/S AIX 5.3 > > > > I am working on one of my inherited instances and I am wondering when > > fragmentation becomes advantageous. More specifically, I have a table > with > > approx. 300,000 rows. Would fragmentation (by expression) help me on this > or > > is it just too small to make much of a difference. This of course assumes > that > > my fragmentation scheme and my where clauses all look like they should. > > > > I know that there is not an exact answer but does anyone have any > practical > > rule of thumb numbers? > > 1M rows: at least own dbspace > 10M rows: consider fragmenting > 100M rows: must fragment > > I generally aim to have no more than 50M rows per fragment. > > I really wouldn't pay any attention to a 300K row table unless it was > unusually "hot". > > -- > Cheers, > Obnoxio The Clown > > http://obotheclown.blogspot.com > I will now proceed to pleasure myself with this fish. > > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. > > --20cf307f37fec67f4604a7e22eb7