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Home -> Community -> Usenet -> c.d.o.server -> Re: Re: A transaction profile question - block growth always groups of 5?
<61.12.128.6 [Igor Laletin]> wrote in message
news:9d8hf262597_at_news1.newsguy.com...
> >
> > <203.101.17.58 [Igor Laletin]> wrote in message
> > news:9d5jrp62upr_at_news2.newsguy.com...
> > > > Igor: read your books.
> > >
> > > Where is it written that next extent always gets rounded up to the
nearest
> > 5 blocks? Reference, please!
> >
> > Well, for starters: http://www.ixora.com.au/tips/creation/extents.htm
> >
> > ...in which it becomes clear that I made one (albeit significant)
omission:
> > if you ask for LESS than 5 blocks, you get what you ask for. But if you
ask
> > for anything else, it gets rounded up. Ask for 7, you'll get 10. Ask
for
> > 44, you'll get 45. Ask for 3, you'll get 3.
> >
> > >
> > > > I didn't just invent this stuff.
> > >
> > > You probably did :) Let's check it out in 8.1.7 but I'm pretty sure
it's
> > the same in other versions.
> >
> > "pretty sure"? Nice to be so authoratitive.
>
> OK, you are right here. There is no need to be "so authoratitive" so I
take it back.
> And, yes, it is nice :) > >
> > Wrong. Howard: read your books. > http://www.ixora.com.au/tips/creation/extents.htm > "Extents may be enlarged further if their allocation would otherwise leavea free space fragment of less than 5 blocks." >
> So you get all 12. > > ... And 12 blocks, unless I'm very much mistaken, sounds suspiciously likenot a rounding up to 5 blocks or multiples thereof to me :) >
In other words, to avoid fragmentation in the first place, Oracle may decide NOT to round to multiples of 5. Which is entirely the opposite of what you stated originally ("Yes, it can get up to 4 blocks more than you requested. _If_ the free space is fragmented in such a way Oracle couldn't find anything better."), and agrees with my statement that 'fragmentation does not cause [rounding]' -because what you have here is potential fragmentation *preventing* the rounding. I agree that in this quantum age, concepts of causality can be confusing, but not that much in this case, surely.
[Snip]
HJR Received on Tue May 08 2001 - 16:04:37 CDT