MORE INFORMATION
Exchange 2000 Support of Windows 2000 Datacenter Server
What Versions of Exchange 2000 Are Supported with Windows 2000 Datacenter Server?
The following version of Exchange 2000 are supported with Windows
2000 Datacenter Server:
- Exchange 2000 Enterprise Server with Exchange 2000 SP1 or
later
The following versions of Exchange 2000 are not supported on
Windows 2000 Datacenter Server:
- Exchange 2000 Enterprise Server (RTM version)
- Exchange 2000 Standard Server (RTM version)
- Exchange 2000 Standard Server with Exchange 2000 SP1 or
later
As with any Windows 2000 Datacenter Server solution, the
hardware must also be certified. Because of the many design considerations in
Exchange 2000, Exchange 2000 Enterprise Server does not fully take advantage of
some of the features that Windows 2000 Datacenter Server offers.
Multiple Processor Support
Windows 2000 Datacenter Server supports 32 processors on a single
server. Exchange 2000 SP1 mailbox servers only scale well to 8 processors on a
server. Partition 32-processor computers into four 8-processor servers by using
hardware partitioning. If you are running Exchange 2000 SP1 on servers that
have more than 8 processors, you are using processor resources inefficiently;
avoid that situation. Exchange 2000 is a distributed program and is designed to
scale out very effectively. For additional information about how to size
processor resources, see the following resources:
- The "Microsoft Exchange 2000 Front-End Server and SMTP
Gateway Hardware Scalability Guide" white paper, which is available at the
following Microsoft Web site:
- The "Microsoft Exchange 2000 Server Back-End Mailbox
Scalability" white paper, which is available at the following Microsoft Web
site:
Process Settings
Windows 2000 Datacenter Server includes a Process Control feature
that server administrators can use to limit the amount of memory that
individual processes consume and configure processor affinity on a per-process
basis.
Memory
On Windows 2000 Datacenter Servers-based computers that are
running programs other than Exchange 2000, limit the Exchange 2000 information
store working set by using Process Control. Because the
/3GB flag is not likely to be set in the Boot.ini file when other
programs (such as Microsoft SQL Server 2000) are running on a Windows 2000
Datacenter Server-based computer, a working set limit of 600 megabytes (MBs)
helps ensure that the information store's 2-gigabyte (GB) virtual address space
allocation is not exceeded.
Processor
You can extend Exchange 2000 multiple-processor scalability by
setting processor affinity. In a sample test, the following results were
obtained:
- Majority Post Office Protocol version 3 (POP3)/Simple Mail
Transfer Protocol (SMTP) mix, with 10 percent load provided by MAPI
- 8 processors total (550 megahertz [MHz] Xeon 1 MB L2
Cache)
- 3x550 MHz processor set for the inetinfo process
- 5x550 MHz processor set for the store process
- Results: 67 percent processor usage with 14,950 context
switches per second
- Results with no affinity set: 69 percent processor usage
with 16,098 context switches per second
If you set affinity, both context switching and CPU usage
decrease.
32 Gigabyte Memory Support
Another prominent Windows 2000 Datacenter Server feature is
support for up to 32 GB of RAM. Programs can support this much memory by using
one or a combination of the following methods. Exchange 2000 does not use
memory beyond 4 GB on a server efficiently; you should not configure Exchange
2000 servers with more than 4 GB of memory.
Per-Process Memory Limitations
By default, Windows 2000 reserves 2 GB of virtual address space
for the kernel and 2 GB of virtual address space for every different process
that is running on the computer. This limits each process from using more than
2 GB of memory. If the
/3GB flag is added to the Boot.ini file, Windows 2000 reserves only 1
GB for the kernel, which provides 3 GB of virtual address space for each
process.
For more information,
click the following article number to view the article in the Microsoft
Knowledge Base:
266096
Exchange 2000 requires /3GB switch with more than 1 gigabyte of physical RAM
Instancing
Instancing refers to the ability to run multiple instances of a
program as separate processes on the same computer (for example, running
multiple copies of Microsoft Notepad). Each process is limited to either 2 or 3
GB of virtual address space (depending on use of the
/3GB Boot.ini flag as described above). If you use instancing, you
allow the program to use more than 3 GB of a server's memory resources. If you
have four instances of Inetinfo.exe, you have the potential to use 4 times 3 GB
of memory (12 GB).
Exchange 2000 SP1 does not support instancing.
Physical Address Extension/AWE
Windows 2000 Datacenter Server extends the Physical Address
Extension (PAE) feature of Windows 2000 Advanced Server to 32 GB. This enables
programs that were written to this API to make use of up to 32 GB of physical
memory. Placing
/PAE in the Boot.ini file enables Windows 2000 to use memory beyond 4
GB. Exchange 2000 does not make use of this application programming interface
(API) and receives very little performance benefit on Windows 2000 Datacenter
Server-based computers that are enabled for PAE. On servers with more than 16
GB of memory, PAE must reserve more kernel memory space so that the
/3GB switch cannot be used. If the
/3GB switch and the
/PAE switch are used in tandem on a computer with 32 GB of memory, PAE
is able to access only the first 16 GB (this information is displayed in
Windows 2000 Task Manager). If you remove the
/3GB flag from the Boot.ini file, you can access all 32 GB of memory
(with a program that is written to the AWE API), but this might cause problems
for Exchange 2000. Depending on the number of storage groups or Messaging
Databases (MDBs) that are configured for an Exchange 2000 server, Exchange may
run out of virtual address space. The more storage groups or MDBs that are
configured on a server, the more virtual address space is consumed. More
specifically, Exchange 2000 may run out of virtual address space on a server
that has more than 1 GB of physical RAM and does not have the
/3GB flag set in the Boot.ini file. If you place
/PAE in the Boot.ini file, you enable Windows 2000 to use memory
beyond 8 GB. AWE is the API that is exposed when this switch is enabled.
Programs that make use of this API can allocate memory beyond 8 GB, up to 32
GB.
Memory Usage Summary
Exchange 2000 servers work well with the
/3GB switch (and its use is required on servers with more than 1 GB of
physical memory), but Exchange 2000 does not support instancing or PAE and AWE.
This limits an Exchange 2000 server to about 4 GB of usable memory. Installing
more than 4 GB of physical memory on an Exchange 2000 SP1 server is not
recommended.
Example Exchange 2000 Enterprise Server SP1 and Windows 2000 Datacenter Server Configurations
With Exchange 2000 Enterprise Server SP1 running on a
32-processor server:
- 32-processor Windows 2000 Datacenter Server
- 16 GB of RAM
Configuration: partition the server into four hardware
partitions. Make each hardware partition of eight processors and 4 GB of
memory. Include the
/3gb switch in each of the hardware partitions' Boot.ini files.
With Exchange 2000 Enterprise Server SP1 running on a 32-processor
server with another Windows 2000 Datacenter Server-certified program, such as
Microsoft SQL Server 2000 (multiple hardware partitions):
- 32-processor Windows 2000 Datacenter Server
- 32 GB of RAM
Configuration: partition the server into two hardware
partitions. The first hardware partition, to be used for Exchange 2000, should
be made up of eight processors and 4 GB of memory. The second hardware
partition, which is used for SQL Server 2000, should be made up of 24
processors and configured with 24 GB of RAM. Include the
/3gb switch in the Exchange 2000 hardware partition's Boot.ini file
and include the
/PAE switch in the SQL Server 2000 hardware partition's Boot.ini
file.
NOTE: This is the recommended method for combining Exchange 2000 with
other Windows 2000 Server Datacenter Server programs on a single hardware
platform.
With Exchange 2000 Enterprise Server SP1 running on a
32-processor server with another Windows 2000 Datacenter Server-certified
program such as SQL Server 2000 (single hardware partition, not recommended):
- 32 processor Windows 2000 Datacenter Server
- 32 GB of RAM
Configuration: partition the server into a single hardware
partition that is made up of 32 processors and 32 GB of RAM. Include the
/PAE switch in the hardware partition's Boot.ini file. By not
including the
/3gb switch, you limit the Exchange 2000 information store to 2 GB of
virtual address space. You must exclude the
/3gb switch to enable the server to see more than 16 GB of RAM.
Process Control Settings
Note the following information about process control settings
- Configure the following Exchange 2000 processes to use only
the first four to eight processors:
- Exchange 2000 information store (Store.exe)
- Internet Information service (Inetinfo.exe)
- Exchange 2000 System Attendant (Mad.exe)
- Exchange 2000 message transfer agent
(Emsmta.exe)
- Configure the Exchange 2000 information store (Store.exe)
process to be able to use only 1 GB of working set.
- The Exchange 2000 configuration in this mixed scenario
(virtual address space) benefits from using fewer database storage groups (one
storage group is recommended for this configuration).
- Configure SQL Server 2000 to use only the remaining 24 or
28 processors and 30 GB of memory.
NOTE: This is not a recommended method for combining Exchange 2000
with other Windows 2000 Datacenter Server programs on a single hardware
platform. Exchange 2000 is less efficient in this scenario. It is recommended
that you place Exchange 2000 on a separate hardware partition than other
Windows 2000 Datacenter Server programs.
For additional information,
visit the following Microsoft Exchange 2000 Server Web site:
For more information about the Datacenter program and other BackOffice
programs, click the following article numbers to view the articles in the
Microsoft Knowledge Base:
266650
Information About BackOffice Program Support on Windows 2000 Datacenter Server-Based Computers
265173 Datacenter Program and Windows 2000 Datacenter Server Product