IBM x3850 X5, Руководство по внедрению

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IBM eX5 Implementation Guide
Figure 6-6 on page 229 shows the Memory configuration panel with your choice of performing
memory sparing (Memory Spare Mode) or memory mirroring (memory mirror mode), but not
both options at the same time. Select the desired option and reboot the server. If your
memory population order does not support the requested option, the server reports a
memory configuration error during the next reboot.
See 3.8.4, “Memory mirroring” on page 87 for the correct memory population order to support
memory mirroring or sparing.
6.4 Attaching the MAX5 memory expansion unit
On top of the 1 terabyte (TB) of memory that you can configure on System x3850 X5, you can
also configure an additional half of a TB of memory in the MAX5 memory expansion unit and
attach the MAX5 to the server to increase the overall memory access performance and
capacity.
It is best to use MAX5 with applications that can benefit from the increase in overall memory
capacity. The most significant performance gains are in applications that
require the
additional memory that MAX5 can provide. If an application does not need the extra memory,
the potential for performance gains is reduced.
The best way to populate memory DIMMs in the server and the MAX5 depends on how the
applications being run address memory and the total amount of memory that is needed by the
application. However, consider the following general rules:
򐂰 Always populate the DIMM sockets in the server first before installing DIMMs in the MAX5.
Local memory has higher bandwidth and lower latency than MAX5 memory. MAX5
memory is limited by the speed of the QPI link.
򐂰 Where possible, install DIMMs so that Hemisphere Mode is enabled. Without Hemisphere
Mode, performance can suffer considerably.
򐂰 You can use the MAX5 on an x3850 X5 that has only two processors installed. However,
you get the best performance by having all four processors installed, installing all memory
cards, and populating those memory cards fully with memory DIMMs.
򐂰 MAX5 adds an additional path to memory through dedicated QPI ports, resulting in
potentially greater memory bandwidth. There can be instances where it is better to
reserve DIMMs for use in the MAX5.
6.4.1 Before you attach the MAX5
Before you can attach and use the MAX5, the System x3850 X5 requires that you install the
firmware that is shown in Table 6-2.
Table 6-2 Minimum firmware levels to support the MAX5 memory expansion unit
The MAX5 also has Field Programmable Gate Array (FPGA) firmware that resides on it. The
MAX5 firmware is updated at the same time that the server to which it is attached has its
Type Version Build
IMM 1.19 YUOO75X
UEFI 1.32 G0E131A
FPGA 1.02 G0UD43A