Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> comp.databases.theory -> Re: Concurrency in an RDB

Re: Concurrency in an RDB

From: David <davidbl_at_iinet.net.au>
Date: 25 Dec 2006 16:54:55 -0800
Message-ID: <1167094495.395574.115830@73g2000cwn.googlegroups.com>

paul c wrote:
> David wrote:
> ...
> > Despite the logical purity there are disadvantages to be considered.
> > Modern CPUs are quite adept at manipulating strings in the normal
> > representation. The space and time overheads of your suggestion are
> > significant.
> > ...
>
> Actually relatively less adept than they used to be, ie., the
> instruction sets have stagnated for decades and when applied to a
> sequential string incur all kinds of cache misses on the latest cpu's
> which are so much faster than the memory they use, ie., they don't come
> close to the advertised cpu speed.

Nevertheless I wouldn't be surprised if the string manipulation is 100 times slower with the relational approach. Each step through a head-tail list would typically involve an independent search through a BTree.

David Received on Mon Dec 25 2006 - 18:54:55 CST

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US