IBM X3850 X6 User Manual

158 IBM System x3850 X6 and x3950 X6 Planning and Implementation Guide
PCIe performance
The x3850 X6 and x3950 X6 offer a large quantity of PCIe slots. To ensure the best possible
performance, it is important to understand the design of the servers and how the PCIe slots
connect to each processor.
Figure 5-34 shows processor-to-slot PCIe connectivity for the x3850 X6.
Figure 5-34 PCIe slot connectivity in the x3850 X6
For best performance, consider these suggestions:
򐂰 Ensure that the slot used for an adapter has the necessary bandwidth. For example, slot 8
(in the Primary I/O Book) is an x8 wired slot, but can physically accept an x16 adapter.
Performance will be negatively impacted if an x16 adapter is installed in that slot.
򐂰 Balance the PCIe load across all processors. This ensures a distributed workload and
reduces the chance of performance bottlenecks.
򐂰 Use processor affinity in the operating system to tie application threads that use PCIe
resources the most to the processor that connects to that PCIe device.
QPI links
Intel
Xeon
CPU 1
Slot 7: PCIe 3.0 x16 (x16)
Slot 9: PCIe 3.0 x16 (x16)
Slot 10: Mezz LOM (x8)
Slot 12: PCIe 3.0 x16 (x8)
Intel
Xeon
CPU 2
Slot 8: PCIe 3.0 x16 (x8)
Slot 11: PCIe 3.0 x16 (x8)
Intel
Xeon
CPU 4
Intel
Xeon
CPU 3
Slot 1
Slot 2
Slot 3
Slot 4
Slot 5
Slot 6
Storage Book
Primary I/O Book
Optional I/O Book in Bay 2
Optional I/O Book in Bay 1
PCIe 3.0 lanes
Optional I/O Books can be either:
Half-length I/O Book
• PCIe 3.0 x16 slot (x16 wired)
• PCIe 3.0 x8 slot (x8 wired)
• PCIe 3.0 x8 slot (x8 wired)
Full-length I/O Book
• PCIe 3.0 x16 (x16 wired)
• PCIe 3.0 x16 (x16 wired)
• PCIe 2.0 x8 slot (x4 wired)

IBM X3850 X6 Specifications

General

Chipset	Intel C602J
Network Controller	Integrated quad-port Gigabit Ethernet
Processor	Up to four Intel Xeon E7-4800 v2 series processors or Intel Xeon E7-8800 v2 series processors
Memory	Up to 6 TB of DDR3 ECC Registered DIMMs (RDIMMs) or Load-Reduced DIMMs (LRDIMMs)
Form Factor	4U rack server
Storage	Up to 24x 2.5" hot-swap SAS/SATA HDDs or SSDs
Expansion Slots	Up to 11 PCIe 3.0 slots
Power Supply	Up to four 1400W or 900W hot-swap power supplies
Memory Type	DDR3 RDIMM/LRDIMM
Storage Controller	ServeRAID M5210 SAS/SATA controller
RAID Support	RAID 0, 1, 5, 6, 10, 50, 60
Operating System Support	Windows Server, Red Hat Enterprise Linux, SUSE Linux Enterprise Server, VMware