IBM NeXtScale System, Планирование и руководство по внедрению

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IBM NeXtScale System Planning and Implementation Guide
Smaller rooms are possible with air curtains, cold air and warm air separation
ducting, fans or blowers, or other airflow modification schemes. These typically
create restricted spaces for airflow, which are windy, noisy, inflexible in their
layout, and difficult to move around in.
Another approach is to contain a single rack or a row of racks in purpose built
enclosure with its own air movement and cooling equipment. When multiplied by
several racks or rows of racks, this approach is expensive and less space
efficient. It also often requires the rack or row to be powered off if the enclosure
must be opened for maintenance of the equipment or the enclosure.
IBM considered the merits of these options, and suggests the use of rear door
heat exchangers, as described in 5.5, “Rear Door Heat Exchanger” on page 141.
This option is a relatively low-cost, low-complexity, space, and power efficient
solution to the cooling challenge.
5.3 Density
With IBM NeXtScale System, most data centers should sustain a density
increase of approximately 28% as compared to iDataPlex, IBM’s previous
high-density server design, even with 6U in each 42U rack that is reserved for
switches or cabling. These server types are compared in Figure 5-3 and uses an
area 10 floor tile-wide by 10 floor tile deep-rack. NeXtScale servers can easily
provide double the density of 1U rack server configurations.
Figure 5-3 Increase in server density with NeXtScale compared to iDataPlex
The examples that are shown in Figure 5-3 are at the higher end of the density
spectrum. They are meant to show what is possible with high-density designs.
= 84 iDataPlex servers = 72 NeXtScale servers
20 racks x
84 servers
= 1680 servers
30 racks x
72 servers
= 2160 servers