Re: RES: pg_dump slow - Mailing list pgsql-performance

> By default W2K systems often had a default TCP/IP packet size of 576B
> and a tiny RWIN.  Optimal for analog modems talking over noisy POTS
> lines, but horrible for everything else

wrong. default MTU for windows 2000 server is 1500, as was NT4.
http://support.microsoft.com/?id=140375

However tweaking rwin is certainly something to look at.

> >If you're happy that doesn't affect you then I'd look at the disk
> >system - perhaps XP has newer drivers than Win2k.
> I'll reiterate: Do _not_ run a production DB server on W2K.  M$ has
> obsoleted the platform and that it is not supported _nor_ any of
> reliable, secure, etc. etc.

wrong again. WIN2k gets free security hotfixes and paid support until
2010.
http://www.microsoft.com/windows2000/support/lifecycle/

> A W2K based DB server, particularly one with a connection to the
> Internet, is a ticking time bomb at this point.
> Get off W2K as a production platform ASAP.  Take to your
> CEO/Dean/whatever you call your Fearless Leader if you have to.

wrong again!!  There is every reason to believe win2k is *more* secure
than win2003 sever because it is a more stable platform.  This of course
depends on what other services are running, firewall issues, etc etc.

>> Economically and probably performance wise, it's best to use an Open
> Source OS like Linux or *BSD.  However, if you must use M$, at least
> use OS's that M$ is actively supporting.

I encourage use of open source software.  However encouraging other
people to spontaneously switch hardware/software platforms (especially
when they just stated when win2k is a requirement) is just or at least
not helpful.

> Despite M$ marketing propaganda and a post in this thread to the
> contrary, you =CAN= often run a production DB server under WinXP and
> not pay M$ their usurious licensing fees for W2003 Server or any of
> their other products with "server" in the title.  How much RAM and

you are on a roll here.  You must not be aware of 10 connection limit
for win2k pro and winxp pro.

http://winhlp.com/WxConnectionLimit.htm

There are hackerish ways of getting around this which are illegal.
Cheating to get around this by pooling connections via tcp proxy for
example is also against EULA (and, in my opinion, unethical).

> how many CPUs you want in your DB server is the main issue.  For a
> 1P, <= 4GB RAM vanilla box, WinXp will work just fine.

Now, who is guilty of propaganda here?  Also, your comments regarding
hard disks while correct in the general sense are not helpful.  This is
clearly not a disk bandwidth problem.

> >What do the MS performance-charts show is happening? Specifically,
> >CPU and disk I/O.
> His original post said ~3% CPU under W2K and ~70% CPU under WinXP

Slow performance in extraction of bytea column strongly suggests tcp/ip.
issue.  I bet if you blanked out bytea column pg_dump will be fast.

Franlin: are you making pg_dump from local or remote box and is this a
clean install?  Try fresh patched win2k install and see what happens.

Merlin