5.4.1 Mailbox Server CPU Planning
Plan the mailbox server performance based on the performance requirement of each mailbox user. Microsoft provides the CPU and memory estimates based on message activity, as shown in the following table:
Table 5-5 Database cache and CPU estimates based on message activity
Messages Send or Received Per Mailbox Per Day
Database Cache Per Mailbox in Megabytes (MB)
Megacycles for Active Mailbox or Stand-Alone Mailbox Megacycles for Passive Mailbox 50 3 1 0.15 100 6 2 0.30 150 9 3 0.45 200 12 4 0.60 250 15 5 0.75 300 18 6 0.90 350 21 7 1.05 400 24 8 1.20 450 27 9 1.35 500 30 10 1.5
You must increase the megacycles per active mailbox by 10 percent for each additional database copy after one active copy.
5.4.2 Mailbox Server CPU Calculation Capacity Calculation
The megacycle is an estimate based on Intel Xeon x5470 3.33 GHz processor (2 x 4 core). A 3.33 GHz process core equals the performance throughput of 3300 megacycles. You can
compare the platform with the server platform tested by Standard Performance Evaluation Corporation (SPEC) to estimate the configuration of other processors. For details, see the results of SPEC CPU2006 on the Standard Performance Evaluation Corporation website. For example, if a server with Intel Xeon E5-2640 2.2 GHz process (2 CPU x 8 cores) is deployed, the result of SPECint_rate2006 is 464, and the value per core is 29 (value per core on the new platform in the formula). The SPECint_rate2006 result of the baseline Intel Xeon x5470 3.33 GHz processor (2CPU x 4 cores) is 150, and the value per core is 18.75 (baseline value per core in the formula). Use the following formula to calculate the adjusted megacycle of the server used in the solution:
(Value per core on the new platform x Hz per core on the baseline platform)/baseline value per core = The adjusted megacycle per core
Perform the following operations to determine the server CPU requirements: 1. Plan the number of servers.
2. Calculate the maximum number of active mailboxes that can be supported by each mailbox server based on the activation model.
3. Calculate the CPU requirement of the active mailbox.
4. Calculate the CPU requirement of the passive mailbox server based on the fault model. After a server is down, the worst result can be that there is no passive mailbox.
5. Add the CPU required by active mailbox servers to the CPU required by passive mailbox servers to get the total CPU requirement, and apply the total CPU requirement to a hardware platform. It is advisable set the CPU usage threshold of the independent server (without faults) to 70% or lower in peak hours. As for the three-node Mailbox server that allows only one faulty node, it is advisable to set its CPU usage threshold to 80% or lower in peak hours (when a node is down). In the best practice, the mailbox server chosen by 9000 mailbox users is configured with a 16-core Intel Xeon E5-2640 2.2 GHz CPU processor.
5.4.3 Mailbox Server Memory Planning
The memory configuration of Exchange Server role includes the memory configuration of Mailbox Server and Client Access Server. To ensure that there is sufficient memory for ESE database to run properly, the physical memory volume of each database count-based server must meet the minimum requirement. The minimum requirement applies to both active and passive database copies. The following table lists the minimum memory requirements of a Mailbox Server.
Table 5-6 Minimum memory requirement of a Mailbox Server
Database Count Minimum Physical Memory of Exchange
1-10 2 GB 11-20 4 GB 21-30 6 GB 31-40 8 GB 41-50 10 GB 51-60 12 GB 61-70 14 GB
71-80 16 GB
81-90 18 GB
91-100 20 GB
The Mailbox Server memory configuration is equal to the memory the mailbox consumes in real time or the maximum memory supported by Exchange Server role, whichever is greater. After the database cache is determined, you need to determine the minimum memory requirement of each server to ensure that the memory can meet the requirement of database cache. You must take into account the database cache when adjusting the memory requirement of a server to ensure, so that the physical memory of a server can meet the requirement of the number of mailboxes when the number of user's configuration files is fixed. The following table describes the default mailbox cache size on a single mailbox server role and multiple mailbox server roles:
Table 5-7 Default mailbox database cache size
Server Physical
Memory (RAM) Database Cache Size (Only Mailbox Server Role) Database Cache Size (Multiple Server Roles)
2 GB 512 MB Not Supported 4 GB 1 GB Not Supported 8 GB 3.6 GB 2 GB 16 GB 10.6 GB 8 GB 24 GB 17.6 GB 14 GB 32 GB 24.4 GB 20 GB 48 GB 39.2 GB 32 GB 64 GB 53.6 GB 44 GB 96 GB 82.4 GB 68 GB 128 GB 111.2 GB 92 GB
Perform the following operations to determine the server memory requirements:
1. Multiply the number of mailboxes by user's configuration file-based memory requirement to obtain the required database cache size.
2. Determine the required physical memory by determining the database cache that can be provided by the server configuration.
3. In the best practice, 32 GB memory is configured in the server that is required by 9000 mailbox users.
5.4.4 Host Multipathing Configuration
The best practice provides storage resources on an FC SAN architecture, and the optical switches that provide redundancy also provide multiple paths between the host and storage. This makes multipathing software necessary for choosing the optimal path.
It is advisable to run the following commands on each ESXi host that is connected by SSH to bear virtual desktops.
esxcli storage nmp satp rule add --satp=VMW_SATP_ALUA --vendor=”HUAWEI” --description “OceanStor 18000”
esxcli storage nmp satp set --default-psp=VMW_PSP_FIXED --satp VMW_SATP_ALUA reboot
Because Huawei storage's multipathing software for VMware ESXi is being certified by VMware, the best practice uses the ALUA protocol that adapts to the VMware multipathing software.
5.4.5 NTFS Allocation Unit Size
The page size of Exchange 2010 is 32 KB. The NTFS allocation unit size must be larger than 32 KB. In a real-world scenario, it is advisable to set the NTFS allocation unit size to 64 KB.
5.4.6 HBA Driver
6
Test Results of Best Practice
This chapter describes the ESRP test results of the solution. You can find the detailed ESRP test report in HTML in the attachments of this PDF file.
This solution uses Microsoft Jetstress 2010 for verification to ensure that the storage design meets disk I/O and capacity requirements.