> > I'm author and maintainer of ZABBIX and the manual. I would like to add
> > some comments to the thread.
>
> just so you know, I brought this up after taking a look at the zabbix
> software, which is in my opinion very excellent. I came across a
> little strong in my comments and peter e was correct in pointing out
> that the performance related comments were not 'fud'. I felt a little
> bad after opening this thread but you have to take this in context of
> the bigger picture. The postgresql poeple have been dealing with
> (sometimes) unfounded prejudices for years.
No worries! :)
> > Unfortunately PostgreSQL performs much slower than MySQL doing large
> > number of updates for one single table. By its nature ZABBIX requires
> > to execute hundreds of updates per second for large installations.
> > PostgreSQL cannot handle this nicely.
> >
> > Do a simple test to see my point:
> >
> > 1. create table test (id int4, aaa int4, primary key (id));
> > 2. insert into test values (0,1);
> > 3. Execute "update test set aaa=1 where id=0;" in an endless loop
>
> this is a very contrived test:
> 1. nothing really going on
> 2. no data
> 3. single user test
> 4. zabbix doesn't do this, nor does anything else
> 5. proves nothing.
>
> zabbix is a bit more complex than that with multiple users, tables and
> the ocassional join. With a high number of servers in play things
> might go differently than you expect.
I cannot agree. Yes, ZABBIX software is much more coplex than the test
here. But performance of core functions of ZABBIX Server depends on
speed of update operations very much. The goal of the test was to
demonstrate very fast performance degradation of the updates.
I'm sure PostgreSQL would perform nicely for a large database with
large number of users, but I just wanted to prove my statement from the
manual.
> ...
> well, I am playing with zabbix with the possible eventuality of
> rolling it out in our servers I might be able to get you some hard
> data on performance. By the way, I'm currently managing a
> spectactularly large mysql database which is getting moved to
> postgresql with the next release of the software -- in part because I
> was able to show that postgresql gave much more reliable performance
> in high load envirnonments.
>
> In light of this discussion, I might be interested in running a little
> test to see how zabbix would hold up on postgresql under a
> artificially high load. If I was to show that things were quite so
> one-sided as you assumed, would you be willing to say as much in your
> documentation? :-)
I would be very interested in any real-life experience running large
ZABBIX installation under PostgreSQL. Feel free to send me your
results. Yes, I'm ready to change the manual, no doubt! :)
Cheers,
Alexei