Re: [PATCHES] How can I use 2GB of shared buffers on Windows?

From: "Magnus Hagander" <magnus(at)hagander(dot)net>
> hnetcfg.dll is a part of Windows. "Home Networking Configuration
> Manager". LPK.DLL is also a part of Windows - it's the language
pack.

Thank you for information.

> On Thu, Feb 08, 2007 at 09:50:26PM +0900, Takayuki Tsunakawa wrote:
>> When I try to start PostgreSQL 8.2.1 on Windows 2003 Server with
>> shared_buffers=1024MB, I get the following error messages in the
Event
>> Log (with log_min_messages=debug5) and can't start PostgreSQL:
>
> Is this for testing, or for production? From what I've heard, you
would
> normally never want that much shared memory - I've seen more reports
on
> taht you shuld keep it as low as possible, really. For performance
> reasons.

For testing. I wanted to place all data in shared buffers to
eliminate reads from disk while I run pgbench repeatedly (actually
most reads should come from kernel cache, though.)

Does PostgreSQL for Windows have any problem when using a large
database cache unlike UNIX versions? I'm excited about your current
great work to enable building all of PostgreSQL with MSVC. I thought
you are aiming at making PostgreSQL 64-bit on Windows in the near
future (though you may not have signified in ML.) I'm afraid MinGW
will not extend to 64-bit (for x64 and Itanium) at least reliably and
immediately, due to the difference of data model -- 'long' is still
32-bit in 64-bit applications on Windows. I thought Magnus-san got
worried about it and started the activity of completely switching to
MSVC.

BTW, the current PostgreSQL for Windows is very slow, isn't it? I
compared the performance of PostgreSQL 8.2.x for Linux (RHEL4 for x86,
kernel 2.6.x) and Windows Server 2003. I ran 'pgbench -c32 -t500' on
the same machine with the same disk layout for data files and WAL,
i.e. they are stored on separate disks. The settings in
postgresql.conf is the same, except for wal_sync_method -- it is set
to open_sync on Linux and open_datasync on Windows, because they are
the best for each platform.
Linux version shows 1100 tps, but Windows version shows only 450 tps.