Most DB's, regardless of actuall size are using many rows. Currently we
run oracle, and each field in a row is a specific size. As we populate the
DB, over time it slows down. This is because there are NO long contiguous
writes. Even with long contiguous writes slow down would occurr, but in a
different manner. Not all DBs are created equally, I understand, but so
far, there seems to be that one factor all DBs have in common, the amount
of data that can be inserted into the db in at one time. This of course is
a combination of OS, FS, and DB tuning, and retuning. So, that's why I say
that. It's not as though the IRS's databases are huge contiguous tables,
they're all split into rows, columns, and fields. As well as different
partitions, which can help with performance, but that's usually making a
large job smaller to manage it better. Thus, smaller writes are again more
prominent. The contrast I use here is say, reading a huge data file, a
ripped DVD or cd perhaps? A lot of contiguous data in a single file in one
format type. That is a long contiguous read/write operation to access
that file. (as in creation/manipulation) Thus, when playing a ripped dvd
through some kind of player, or streaming that info out to a network host,
you'd expect to get pretty decent throuput from the system. Databases,
until tweaked a lot, usually get I/O bound and have problems getting the
data from point A-B. Again, this relates to read/writes. Reads aren't too
slow for this kind of data anyway, querries are pretty quick, but in the
event that you do bulk inserts, then you'd see a major slowdown, and have
to retune your system.
--
Austin Gonyou
Systems Architect, CCNA
Coremetrics, Inc.
Phone: 512-796-9023
email: austin@xxxxxxxxxxxxxxx
On Wed, 16 May 2001, Keith Matthews wrote:
> On Wed, 16 May 2001 11:18:58 -0500 (CDT) Austin Gonyou <Austin Gonyou
> <austin@xxxxxxxxxxxxxxx>> wrote:
>
> > Don't forget, small file tests are what big slow db's are made of. :)
> >
> > --
>
>
> Just what sort of db are you talking about ?
>
>
> --
> Keith Matthews
>
> Frequentous Consultants - Linux Services,
> Oracle development & database administration
>
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