Re: PostgreSQL vs. InnoDB performance

Scott Marlowe <smarlowe(at)g2switchworks(dot)com> writes:

> Also, I wonder how well both databases will survive having power removed
> while under heavy load...

It depends more on the underlying hardware setup (disk/raid array)
than on the any other aspect (like OS). Assuming you have fsync
enabled, of course.

There is a very interesting test that you can do (if you have two
machines) to see what happens if one of your machines suddenly loses
power. You can read about that here:
http://www.livejournal.com/users/brad/2116715.html

Most of todays IDE disks comes with write caching turned on by
default, and if you lose power, you'll lose some of unwriten data for
sure. Turn it off, or if you're using ext3 on Linux 2.6, you can mount
your partitions with barrier=1 option which will make your fsyncs safe
and still let you get some benefits from write caching.

Of course, your production quality database would be on the powerful
SCSI disk array behind a good RAID controller. Question there is have
you bought the (often) additional battery backup for your RAID card?
If notm turn the write caching off, once again, or you WILL lose your
data and corrupt your database if you suddenly lose power.
--
Zlatko