Обсуждение: Re: Open Source Database Routs Competition in New Benchmark Tests

> I wouldn't say that this is exactly the first time we've heard
> about problems with MySQL's famed "speed".  Take the Tim Perdue
> article that came out a while back:

> http://www.phpbuilder.com/columns/tim20000705.php3?page=1

Yes, but the conclusion at that time was that PostgreSQL in general was
slower, but scaled better. So on a heavily loaded site, they would
perform equally well, because PostgreSQL could handle 5 times the load
of MySQL, but MySQL was 5 times faster than PostgreSQL (ot something
like that).

This is the first benchmark saying that PostgreSQL is actually faster
than MySQL. And as we all know, benchmarks can be stretched any way you
like it, so that's why I'd like some comments before I go out and
advocate too strongly :-)

At 11:12 AM 8/15/00 +0200, Kaare Rasmussen wrote:

>This is the first benchmark saying that PostgreSQL is actually faster
>than MySQL. And as we all know, benchmarks can be stretched any way you
>like it, so that's why I'd like some comments before I go out and
>advocate too strongly :-)

Good scaling characteristics are a lot more important than raw speed
for the web environment, at least, where short, quick queries to
personalize content, etc are the rule.  If only a couple of folks
are using the site simultaneously, who cares if it takes an
extra 50 milliseconds to return the page?  If I've got a hundred
users on my site, though, and the database engine "starts falling
apart around 40-50 users", then I'm in deep doo-doo.

In practice, MySQL users have to implement the atomic updating of
a set of tables "by hand" using special locking tables, etc.  All
the cruft surrounding this is not very likely to be more efficient
than the built-in transaction code of a real RDBMS.  When people
talk about the raw speed of MySQL they forget that working around
its table locking granularity and lack of transaction semantics
is a pain that costs CPU as well as programmer cycles.

I came back to Postgres after rejecting it for website development
work when I heard that MVCC was replacing the older table-level
locking model.  I've never been excited about MySQL for the same
reason (among many others).



- Don Baccus, Portland OR <dhogaza@pacifier.com> Nature photos, on-line guides, Pacific Northwest Rare Bird Alert
Serviceand other goodies at http://donb.photo.net.