gaël charrière wrote:
Actually the 2 backends are collocated on the same machine with the
controller precisely because I'm in testing mode. My final goal is to
compare the performance of different cluster architecture without
being impacted by some external noise.
My experience shows that such configuration has such a high variance in
performance measurements that it makes it impractical to draw any useful
conclusion.
With my sequoia architecture, as I explained, I still noticed very
slow responses, even if all my nodes are located on the same machine.
So I don't think it will be better through the network... That's why I
would like to improve it now before involving myself into a much more
complex architecture.
There is very little information going through the network and the main
cost is serialization of data, not the cost of sending on the wires. So
having dedicated resources for each database rather than sharing
resources (cpu, mem, and especially io) will make a difference. Note
that each database commit requires a flush to disk so if you don't use
different disks for each database, performance will be horrendous.
What other architectures are you considering to compare Sequoia with?
Don't hesitate to let me know if your results are different from my
experience.
Emmanuel
On Thu, Jun 26, 2008 at 5:41 PM, Emmanuel Cecchet
<[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>> wrote:
Hi Gael,
1 controller, 2 backends (MySQL 5.1) and 1 recovery (MySQL 5.1)
You don't need group communication with a single controller. The
performance might be altered by the way the group communication
handles loopback delivery.
I can start the controller and enable the backends. I can also
access the cluster and perform some queries. Items appeared on
the backends. Everything seems to work fine.
However, I noticed bad performances, especially for insertion
queries. A simple insertion in a virtual database takes about
0.500 s.
Does anybody already notice that kind of measures? I'm looking
for a way to optimize these queries. I tried different appia
configurations, but I wasn't able to find one which correspond
to what I expected.
>From your config file it looks like the 2 backends are collocated
on the same machine with the controller. This probably defeats the
purpose of both performance scalability and availability, so I
don't know how relevant performance measurements on such
configuration could be. We usually use such config for testing
only (mostly functional) but not for performance.
Don't hesitate to keep us posted with your findings,
Emmanuel
--
Emmanuel Cecchet
FTO @ Frog Thinker
Open Source Development & Consulting
--
Web: http://www.frogthinker.org
email: [EMAIL PROTECTED]
Skype: emmanuel_cecchet
_______________________________________________
Sequoia mailing list
[email protected]
https://forge.continuent.org/mailman/listinfo/sequoia
