Thread: PostgreSQL Replication Server?
The database article at Zend mentioned a replication server for PostgreSQL., available at www.pgsql.com. The press release says the code itself has been put into the CVS tree, but I can't find any documentation on it anywhere. Anyone have any pointers? Gerald.
On Fri, 1 Jun 2001, Gerald Gutierrez wrote: > The database article at Zend mentioned a replication server for > PostgreSQL., available at www.pgsql.com. The press release says the code > itself has been put into the CVS tree, but I can't find any documentation > on it anywhere. You won't find any documentation, for it seems that none has been written. I was bitten by this fact and had to use an ugly hack to make replication work... without erserver (basically dump and restore at the other side). It works as long as the database is small... Now, erserver seems to work, but it needs a bit hacking around that I hadn't done yet. Maybe when I get it working I'll see to writing something. In the mean time, source code is the only thing that can help you. The code is in contrib/rserv. -- Alvaro Herrera (<alvherre[@]atentus.com>)
On Wed, 6 Jun 2001, Alvaro Herrera wrote: > On Fri, 1 Jun 2001, Gerald Gutierrez wrote: > > Now, erserver seems to work, but it needs a bit hacking around that I > hadn't done yet. Maybe when I get it working I'll see to writing > something. In the mean time, source code is the only thing that can help > you. I forgot to explain: erserver works well "out of the box" for one master / one slave setup. If you need more than one slave, you need some hacking around. If you need more than one master, I doubt it'll work in its current form. -- Alvaro Herrera (<alvherre[@]atentus.com>)
Or try: http://pgreplicator.sourceforge.net/ Haven't used it myself yet, but it looks pretty good... > > Now, erserver seems to work, but it needs a bit hacking around that I > > hadn't done yet. Maybe when I get it working I'll see to writing > > something. In the mean time, source code is the only thing that can help > > you. > > I forgot to explain: erserver works well "out of the box" for one > master / one slave setup. If you need more than one slave, you need some > hacking around. If you need more than one master, I doubt it'll work in > its current form. > > -- > Alvaro Herrera (<alvherre[@]atentus.com>) > > > ---------------------------(end of broadcast)--------------------------- > TIP 4: Don't 'kill -9' the postmaster > >
On Thu, Jun 07, 2001 at 09:06:06AM +0100, Gordan Bobic wrote: > Or try: > > http://pgreplicator.sourceforge.net/ > > Haven't used it myself yet, but it looks pretty good... I tried to build it , but it depends on an extention to tcl (tcl-dp) that I couldn't get working. Admittedly, I gave up pretty easily. But just a warning that you need something which might not be available everywhere, whereas the rserv code depends on Perl. -- ---- Andrew Sullivan 87 Mowat Avenue Liberty RMS Toronto, Ontario Canada <andrew@libertyrms.com> M6K 3E3 +1 416 646 3306 x110
> > The database article at Zend mentioned a replication server for > > PostgreSQL., available at www.pgsql.com. The press release says the code > > itself has been put into the CVS tree, but I can't find any documentation > > on it anywhere. The article at Zend also stated that PostgreSQL could handle 1000 transactions a second with 100 users. This is funny, since my postgresql server (7.1.2) running on a PII 533 with SCSI and 256 mb RAM (HP Server) can't even handle 1000 select statements per second. Not even close. Daniel Akerud
> > > The database article at Zend mentioned a replication server for > > > PostgreSQL., available at www.pgsql.com. The press release says the code > > > itself has been put into the CVS tree, but I can't find any documentation > > > on it anywhere. > > The article at Zend also stated that PostgreSQL could handle 1000 > transactions a second with 100 users. This is funny, since my postgresql > server (7.1.2) running on a PII 533 with SCSI and 256 mb RAM (HP Server) > can't even handle 1000 select statements per second. Not even close. "transactions per second" does not equate to "real-world queries per second". : ) When we were sizing out a machine, a Compaq rep came in and asked how many queries we did in a day, and he told us that a single CPU alpha could handle about ten times that many "transactions per second". The machine we have now is a lot faster than a single Alpha, and is getting overloaded. steve
On Thu, 7 Jun 2001 zilch@home.se wrote: > > > > The database article at Zend mentioned a replication server for > > > PostgreSQL., available at www.pgsql.com. The press release says the code > > > itself has been put into the CVS tree, but I can't find any documentation > > > on it anywhere. > > The article at Zend also stated that PostgreSQL could handle 1000 > transactions a second with 100 users. This is funny, since my postgresql > server (7.1.2) running on a PII 533 with SCSI and 256 mb RAM (HP Server) > can't even handle 1000 select statements per second. Not even close. Small machine, sorry ... move to a Dual-PIII with a gig of RAM and multiple drives striped ... bump the shared memory to use 512Meg of RAM so that alot of caching is being done in memory ... then you have a serious server :) we did some testing where a client was seeing 4k+ TPS *shrug*
The Hermit Hacker wrote: > On Thu, 7 Jun 2001 zilch@home.se wrote: > > > > > > > The database article at Zend mentioned a replication server for > > > > PostgreSQL., available at www.pgsql.com. The press release says the code > > > > itself has been put into the CVS tree, but I can't find any documentation > > > > on it anywhere. > > > > The article at Zend also stated that PostgreSQL could handle 1000 > > transactions a second with 100 users. This is funny, since my postgresql > > server (7.1.2) running on a PII 533 with SCSI and 256 mb RAM (HP Server) > > can't even handle 1000 select statements per second. Not even close. > > Small machine, sorry ... move to a Dual-PIII with a gig of RAM and > multiple drives striped ... bump the shared memory to use 512Meg of RAM so > that alot of caching is being done in memory ... then you have a serious > server :) > > we did some testing where a client was seeing 4k+ TPS *shrug* > So, is one select statement equal to one of these transactions? Seems to me that talking about transactions per second is like talking about instructions per second on a complex instruction-set CPU - depending what you use for an instruction, your answer could vary significantly.
> > we did some testing where a client was seeing 4k+ TPS *shrug* > > So, is one select statement equal to one of these transactions? Seems to me > that talking about transactions per second is like talking about instructions > per second on a complex instruction-set CPU - depending what you use > for an instruction, your answer could vary significantly. Just reading this discussion it sounds to me like empty transactions (ie. a bunch of BEGIN; COMMIT;). Which is a good measure of transaction overhead, but not necessarily real world performance. Greg