Re: request for enhancement: 2K -> 4K

At 11:49 AM 12/15/97 +0000, you wrote: }David Williams wrote: } }> In article <3494a300.1118117@news.xs4all.nl>, Reinoud van Leeuwen }> <reinoud@xs4all.nl> writes }> >On 12 Dec 1997 09:26:16 -0700, Pablo Sanchez <pablo@sgi.com> wrote: }> > }> >>Sybase Inc., }> >> }> >>I'd like to request that we increase the atomic page size }> >>from 2K to 4K. Today's systems I/O subsystems can handle }> >>the larger page sizes. It'd be nice to have pages greater }> >>than 2K for DSS type of applications. OLTP, I don't }> >>believe, would suffer. (Informix uses a 4K page size and }> >>they do pretty well...) with DSS app's, one has }> >>denormalization that tends to create fat rows... how about }> >>it? }> > }> >The disadvantage is that 4 K will be the minumum size for all }> >allocations, resulting in more wasted space in the database... }> >_______________________________________ }> }> With 2Gb (2048Mb) even wasting 20Mb is only 1%! Surely you don't }> size things that 1% more will mean you need to buy another disk? }> }> I come from tge Informix side and I'd like things similar to }> Informix's blobspaces. You have normal database spaces which have }> 2K or 4K pages depending upon the specific port. within blobspaces }> you then define how large a blobpage will be in units of either }> 2K or 4K. Big buffers (up to, I think 32K) are using to access }> blobspaces. }> }> Why can't we just define our own page sizes for each area of disk }> we use? Say in units of 2K or 4K depending upon the machine type? }> }> -- }> David Williams } }The paging functions in the Informix engine were complicated enough to }understand in v5.01 with only 2K pages, and I am unaware of how much it has }increased in the later versions, ie. 6+. I would think that this would not }be approved on the same grounds as you described above. Developing and }looking after this would simply be ugh! As I understand it, even in pre-6.x, the page size for Informix was platform specific. Most ports were done with a 2K page, however some which showed performance advantages with a larger page size, were ported as 4K. Sequent is one example. Jon }-- }Graeme Allison }Technical Support Consultant }Kenan Systems Corporation } } ----------------------------------------------------------------------- Jon C. Vemo jon@etcscan.com Database Administration Deluxe Payment Protection Systems/SCAN Bothell, WA (425) 489-1120 -----------------------------------------------------------------------