IBM 88743BU - System x3950 E, Руководство пользователя

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Planning, Installing, and Managing the IBM System x3950 M2
Hot-add CPU
Building on the existing support for hot-add memory, SQL Server 2008
introduces the installation of additional CPUs in supported server hardware so
that you can use the new CPU resources immediately without downtime. This
feature extends the ability of SQL Server to scale up the available hardware
resources without disrupting the environment. Currently, support is not available
for SQL 2008 hot-add CPU feature with IBM eX4 servers.
2.8 Scale-up or scale-out
The goal of system scalability is to increase performance at a rate that is
proportional to increases in system resources for a given workload. The two
methods to achieving system scalability are:
򐂰 Scale-up: Increasing the capacity of the single system image by adding (in
particular) processors, memory, and disk.
򐂰
Scale-out: Adding systems that can be managed and run together.
2.8.1 Scale-up
Scaling-up is achieved by adding resources, such as memory, processors, and
storage, to an existing system that runs on a single server. It is also referred to as
vertical scaling. The benefit to scaling up is that it is relatively easy, because in
general it requires only hardware or software that is designed to take advantage
of additional memory, processor, and storage resources.
With the mass adoption of virtualization as a means for server consolidation and
driving up resource utilization on under utilized mulit-core processor based
systems, virtualization infrastructures are increasingly required to support larger
numbers of virtual and more diverse workloads with higher levels of software and
hardware redundancy. This has translated to virtualization trends seeking to
deploy virtualization platforms that deliver performance and availability, and also
the agility and flexibility to grow and shrink in line with business demands.
Scale-up systems, such as the IBM eX4 servers, are increasingly being exploited
by NUMA-aware virtualization hypervisors, such as VMware ESX, and the
demands of virtualized workloads.
For example, your database server might start out on a 2-way SMP system with
4 GB of memory and six hard drives. As the database grows in size or the
number of users increases, you can easily scale-up by adding more processors,
memory, and disk resources to maintain the same level of performance. You
might eventually have to replace the server with one that is capable of supporting