Hello,
Le 10/02/2016 08:43, Chris Travers a écrit :
I have never seen database corruption on PostgreSQL that was not a
result of either:
1. Use cases WAY out of the ordinary (and then only years ago and I
reported a bug on this and it was very quickly fixed)
2. Hardware problems
3. Heat management problems (sticking a db server in a hot closet, and
then only indexes were corrupted).
I do think on decent hardware you will have no trouble. In other words,
outside of horrible abuse, PostgreSQL does very well.
Yes, I've seen more than horrible abuses... and I can firmly confirm
that PostgreSQL behaves very reliably, in my humble experience with
PostgreSQL.
Let me tell you about one of the worst use cases I've encountered. I had
set up a server (it was actually my desktop machine that I abandoned on
site, with the name "server" quickly written on it, running with a
Debian Stable GNU/Linux and a PostgreSQL cluster) on one of my clients'
site, in West Africa. A few months after, a colleague called me on the
phone, he was complaining about the server not restarting. He forgot to
mention a few details:
- the power was going down about once to twice per hour during five to ten
minutes each time;
- the UPS battery was dead, it provided about half a second of power during
failures;
- the floor was carefully bloomed daily, but without sprinkling water
on the floor, so that all the laterite dust was floating in the air.
During this phone call, a power failure happened. He told me "I must
restart the server, please hold on", and then I heard a strange noise,
like someone repeatedly banging with a hammer. When he resumed our
telephonic conversation, a few seconds later, I asked him about that
noise; he said "oh, yes, I need to hammer on the power button of the
server; otherwise it won't start"...
Some time later, I did a mission on site. The situation of the poor
little server was absolutely horrible: it was covered with red laterite
dust, the inside of the machine was all red and dusty, the grids in
front of the fans had totally rusted within a few months; people were
literally hammering on it, for the power button was stuck with fine
dust; temperature was around 30°C to 45°C, depending on the season, no
or so few air conditioning, and moisture often close to 100% (you know,
when you see condensation happening indoor, indoor rain is an
interesting phenomena).
I carefully dismantled the machine, cleaned it thoroughly, we moved it
in a slightly cooler area (the boss's office), trying to find a power
outlet which would be stable enough...
So, the context of was, I think, way outside of what I would call a
horrible abuse; but despite these conditions, PostgreSQL did very well,
there has never been any data loss, it was used daily for
mission-critical operations.
So there are my $0.02
And these were my small 0.02€ ;)
À+
Pierre
PS: sorry Chris, I didn't pay attention while replying: I replied to you
only, instead of the list => corrected, sorry for the double entry in
your mailbox.
PPS: how should I behave on this list: should I systematically "reply to
all", or just "reply" to the list? I'm used to a number of mailing
lists where a simple "reply" automatically replies to the list, and the
rule obliges you to *only* use "reply".
On Wed, Feb 10, 2016 at 5:10 AM, ioan ghip <ioan@xxxxxxxxxxxxxxx
<mailto:ioan@xxxxxxxxxxxxxxx>> wrote:
I have a Firebird SQL database running on one of my servers which
has about 50k inserts, about 100k updates and about 30k deletes
every day. There are about 4 million records in 24 tables. I have a
bunch of stored procedures, triggers, events and views that I'm using.
Firebird works fairly well, but from time to time the database gets
corrupted and I couldn't figure out yet (after many years of
running) what's the reason. When this happens I run "gfix -mend
-full -ignore", backup and restore the db and everything is fine
until next problem in a week, or a month.
Is this running as an embedded engine or a standalone server? One thing
about Firebird is that since it is embeddable, in that mode other
application bugs could corrupt the database. In the other case, I would
expect you may want to run hardware diagnostics to rule out hardware
problems going forward. If you find hardware problems fix them first,
then look further.
But the low hanging possible things to look at here are moving from an
embedded mode to a standalone server if applicable, and checking out
your hardware. If these turn out not to be the problem, then I would
recommend moving.
I never used PostgreSQL. Yesterday I installed it on my development
machine and after few tests I saw that it's fairly easy to use.
Does anyone have experience with both, Firebird and PostgreSQL? Is
PostgreSQL way better performing than Firebird? Is it worth the
effort moving away from Firebird? Would I gain stability and
increased performance?
I have never seen database corruption on PostgreSQL that was not a
result of either:
1. Use cases WAY out of the ordinary (and then only years ago and I
reported a bug on this and it was very quickly fixed)
2. Hardware problems
3. Heat management problems (sticking a db server in a hot closet, and
then only indexes were corrupted).
I do think on decent hardware you will have no trouble. In other words,
outside of horrible abuse, PostgreSQL does very well.
The largest PostgreSQL database I have worked with had hundreds of
tables, some containing over a hundred million rows, and took up 9TB+ of
storage. And it processed millions of inserts, deletes, and updates
every day (24x7 scientific computing cluster processing the data in the
db). Granted at that scale performance requires very good hardware and
an attention to detail but with those it runs fine.
I do have experience on both and am generally happier with PostgreSQL
but I can imagine there are cases where the move may be painful. Stored
procedures are one (though probably not so bad). The bigger issue I
think you will run into is case folding. Firebird follows the SQL
standard and folds to upper case. The PostgreSQL community really
doesn't like this and folds to lower case. This can require some
changes in application code to make work properly.
So there are my $0.02
Thanks.
--
Best Wishes,
Chris Travers
Efficito: Hosted Accounting and ERP. Robust and Flexible. No vendor
lock-in.
http://www.efficito.com/learn_more
--
____________________________________________________________________________
Pierre Chevalier
PChGEI: Pierre Chevalier Géologue Et Informaticien
Mesté Duran
32100 Condom
Tél+fax : 09 75 27 45 62
06 37 80 33 64
Émail : pierrechevaliergeolCHEZfree.fr
icq# : 10432285
jabber: pierre.chevalier1967@xxxxxxxxx
http://pierremariechevalier.free.fr/pierre_chevalier_geologue
____________________________________________________________________________
--
Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general
