IBM x3650 - System M2 - 7947 Product Manual - page 5
A highly available and expandable, rack-dense, 2U dual-socket SMP server, for application
serving in Web environments
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improved fault isolation.
For increased availability, the x3650 offers two additional (but mutually exclusive) levels of IBM
Active Memory protection: online
memory mirroring, and online hot-spare memory.
Memory mirroring works much like disk mirroring. The total memory is divided into two channels.
Data is written concurrently to both channels. If a DIMM fails in one of the DIMMs in the primary
channel, it is instantly disabled and the mirrored (backup) memory in the other channel becomes
active (primary) until the failing DIMM is replaced. Mirroring can be accomplished with multiples
of four DIMMs (one pair per memory channel).
When online hot-spare memory is enabled, using single and/or dual-rank DIMMs
one rank is
set aside per branch as online spares in case one of the other ranks fails. The spare rank must
have capacity at least that of the largest active rank. Up to
40GB (using 12 single-rank 4GB
DIMMs) or
44GB (using 12 dual-rank 4GB DIMMs) of memory is available when the hot-spare
feature is active. (The lowest-numbered rank of those with the highest capacity in each branch
is used for the hot-spares.)
Either of these features requires operating system support.
When multiples of four DIMMs (4/8/12) are installed, the x3650 operates in
four-way
interleaved mode, for higher performance. When only two DIMMs are used, the system
defaults to
two-way interleaved mode.
DIMMs must be installed in pairs. Memory is available in kits consisting of two
512MB, 1GB,
2GB or 4GB DIMMs.
High-Performance Adapter Slots
The x3650 provides
four physical x8 (“by 8”) PCI-E (PCI Express) adapter slots standard. Each
is capable of supporting
x1/x4/x8 adapters. Slot 1 is full-length/full-height and Slot 2 is half-
length/full-height. Electrically they are x8 slots as well (meaning that they operate at full x8
4GBps speeds). Slots 3 and 4 are low-profile/full-length slots, wired for x4 speeds (2GBps).
This provides the flexibility to use x8 cards in those slots (although running at x4 speeds.) If
desired, the riser card containing slots
1 and 2 may optionally be replaced with one that
provides
two 64-bit (1Gbps) 133MHz PCI-X slots instead, one full-length/full-height and one
half-length/full-height.
PCI-Express is a high-performance, low-latency, next-generation serial I/O bus that is rapidly
replacing the older parallel PCI and PCI-X buses. A
x8 PCI-E adapter offers approximately four
times the maximum throughput of a 133MHz PCI-X adapter
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. (A
x1 adapter offers throughput
similar to a
66MHz PCI-X slot.)
Because the
SAS, ServeRAID-8k and 8k-l, dual Gigabit Ethernet, systems management and
video controllers are integrated onto the system board, the four adapter slots are all available,
which offers you a wide degree of latitude in expansion options.
Hot-Swap/Redundant Components
System availability is maximized through the extensive use of hot-swap and redundant
components, including:
• Redundant memory protection (with Chipkill protection plus, memory mirroring or online
hot-spare memory enabled)
• Hot-swap, redundant hard disk drives (with RAID-0/1/10 protection standard and RAID-
1E/5/6 optional)
• Hot-swap, redundant power supplies (optional)
• Hot-swap, redundant cooling fans (optional)
Large HDD Storage Capacity
The x3650 offers a choice of disk storage, supporting up to
six (3.5-inch) or eight (2.5-inch)
hot-swap high-performance Serial-Attach SCSI (SAS) drives, or up to six (3.5-inch) hot-swap
Serial-ATA (
SATA) drives:
3.5-inch SAS
• 15,000 RPMs — 73.4, 146.8 or 300GB (1.8TB maximum)
2.5-inch SAS
• 10,000 RPMs — 73.4 or 146.8GB (1.17TB)
• 15,000 RPMs — 73.4GB (587.2GB)
3.5-inch SATA
• 7,200 RPMs — 160, 250, 500, 750GB or 1TB (6.0TB)
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Actual throughput will depend on the adapter vendor’s implementation.