Re: insert performance for win32

> > I've done the tests with rc1. This is still as slow on windows ...
> about
> > 6-10
> > times slower thant linux (via Ip socket). (depending on
> using prepared
> > queries, etc...)
> >
> > By the way, we've tried to insert into the windows database from a
> linux
> > psql
> > client, via the network. In this configuration, inserting is only
> about 2
> > times slower than inserting locally (the linux client had a
> slower CPU
> > 1700Mhz agains 3000).
> > Could it be related to a problem in the windows psql client ?
>
> [OK, I'm bringing this back on-list, and bringing it to
> QingQing's attention, who I secretly hope is the right person
> to be looking at this problem :)]
>
> Just to recap Marc and I have been looking at the performance
> disparity between windows and linux for a single transaction
> statement by statement insert on a very narrow table with no
> keys from a remote client. Marc's observations showed (and I
> verified) that windows is much slower in this case than it
> should be. I gprof'ed both the psql client and the server
> during the insert and didn't see anything seriously out of
> order...unfortunately QQ's latest win32 performance tweaks
> haven't helped.
>
> Marc's observation that by switching to a linux client drops
> time down drastically is really intersing!

Could this be a case of the network being slow, as we've seen a couple
of times before? And if you run psql on the local box, you get it
double.

Do you get a speed difference between the local windows box and a remote
wnidows box?

//Magnus

Le Mercredi 02 Novembre 2005 14:54, Magnus Hagander a écrit :
> > > I've done the tests with rc1. This is still as slow on windows ...
> >
> > about
> >
> > > 6-10
> > > times slower thant linux (via Ip socket). (depending on
> >
> > using prepared
> >
> > > queries, etc...)
> > >
> > > By the way, we've tried to insert into the windows database from a
> >
> > linux
> >
> > > psql
> > > client, via the network. In this configuration, inserting is only
> >
> > about 2
> >
> > > times slower than inserting locally (the linux client had a
> >
> > slower CPU
> >
> > > 1700Mhz agains 3000).
> > > Could it be related to a problem in the windows psql client ?
> >
> > [OK, I'm bringing this back on-list, and bringing it to
> > QingQing's attention, who I secretly hope is the right person
> > to be looking at this problem :)]
> >
> > Just to recap Marc and I have been looking at the performance
> > disparity between windows and linux for a single transaction
> > statement by statement insert on a very narrow table with no
> > keys from a remote client. Marc's observations showed (and I
> > verified) that windows is much slower in this case than it
> > should be. I gprof'ed both the psql client and the server
> > during the insert and didn't see anything seriously out of
> > order...unfortunately QQ's latest win32 performance tweaks
> > haven't helped.
> >
> > Marc's observation that by switching to a linux client drops
> > time down drastically is really intersing!
>
> Could this be a case of the network being slow, as we've seen a couple
> of times before? And if you run psql on the local box, you get it
> double.
>
> Do you get a speed difference between the local windows box and a remote
> wnidows box?
>
> //Magnus
The Windows-Windows test is local (via loopback interface)
The Linux (client) - Windows (server) is via network (100Mbits)

I can't test with 2 windows box ... I haven't got that much (all machines
linux, except the test one...)

"Magnus Hagander" <mha(at)sollentuna(dot)net> writes:
>> Marc's observation that by switching to a linux client drops
>> time down drastically is really intersing!

> Could this be a case of the network being slow,

I'm wondering about nonstandard junk lurking in the TCP stack of the
Windows client machine. Also, I seem to recall something about a "QOS
patch" that people are supposed to apply, or not apply as the case may
be, to get Windows' TCP stack to behave reasonably ... ring a bell?

regards, tom lane