Exchange-Genie

A common question is how many users can an Exchange 2007 server handle and there are a large number of factors that go into that question however I recently had the pleasure of spending a week at a Microsoft MTC where we attempted to see what type of scale and Exchange 2007 mailbox server could handle.

When I told most people I was going to put 100,000 mailboxes on one Exchange 2007 server the first statement tendended to be are you crazy!

Microsoft does not support such a high number of users on a single server but that does not mean the server cannot scale to that load.

Since we where placing such a large number of users we required a lot of storage even with only 100mb mailboxes. As this broke down to around 2,040 users per storage group which required about 200 GB of disk space per storage group x 50 which is 10 TB just for the databases.

A number of vendors have published Exchange 2007 scale tests that have passed the Ecxhange solution review program and thier findings can be found at
http://technet.microsoft.com/en-us/exchange/bb412164.aspx and is a good place to find information on building environments to handle specific users loads.

User Profile:
100mb mailbox limits
Average profile used

User Type

http://msexchangeteam.com/archive/2007/01/16/432222.aspx

Tools used:
Loadgen
http://www.microsoft.com/downloads/details.aspx?familyid=0FDB6F14-1E42-4165-BB17-96C83916C3EC&displaylang=en

Hardware configuration:
1 DC
4×2 Xeon 3.0 Ghz
16GB Ram
HP Proliant D:580 G4
Windows 2008

1 CAS
HP Proliant
Windows 2008
Exchange 2007 SP1 rollup2
16GB Ram
2×4 3.0ghz

1 HUB
Dell Power Edge 2970
2×2 Amd Opt 2222 SE
16GB Ram
Windows 2008
Exchange 2007 Sp1 rollup 2

1 MBX
Windows 2008
Exchange 2007 SP1 rollup2
Dell 6850
4 X 2 core Xeon 3.0 ghz
32GB Ram
Emulex Light Pulse Lpe11000-M4

4 Loadgen servers
worker1
Worker2
Worker3
Worker4

1 EMC CMX-340 SAN
110 15k SAS
16 Sata 2

Mailbox server configuration
50 SG
50 Databases
Each database held 2040 mailboxes

Disk configuration
110 SAS disks
16 SATA II disks
10 LUNS created each using 11 15k SAS drives with Raid 5
We placed 5 databases using a Raid 5 which was stripped across 11 15k SAS drives (not ideal but needed the disk space)
1 LUN was created with 16 SATA drives using a Raid 5 for logs, this LUN was divided into 4 Logical disk (ideally the logs would be on SAS drives however we ran out of SAS disks)

Test run:
1. 2,000 users simulated a 8 hour work day with test to run for 30 minutes

2. 4,000 users simulated a 8 hour work day with test to run for 30 minutes

3. 6,000 users simulated a 8 hour work day with test to run for 30 minutes

4. 8,000 users simulated a 8 hour work day with test to run for 30 minutes
1
5. 10,000 users simulated a 8 hour work day with test to run for 30 minutes

6. 14,000 users simulated a 8 hour work day with test to run for 4 hour

7. 22,000 users simulated a 8 hour work day with test to run for 8 hour

8.50,0000 users simulated a 8 hour work day with test to run for 24 hour

Test Results (perfmon):
coming soon

Comments:

ISSUES:
1. One of the first items that we ran into was the fact we started with 2 worker boxes for loadsim both with 16GB of Ram however there where unable to produce the load we needed to generate once we started to scale. We added to additional servers 1 W2k8 with 32GB Ram and 1 W2k3 x64 with 24GB Ram.

2. Further testing would have to be done to validate this however when online maintaince would run at 1am the processor would go under heavy load for about 30 minutes and the store.exe would consume any free memory.