IBM 170 Servers Manual page 103

Accelerator for System i
Coinciding with the release of i5/OS V5R4, IBM introduces new entry IBM System i models. The
models introduce accelerator technologies and/or L3 cache in order to improve options for clients in the
low-end server space. As an overview, the Accelerator for System i affects two 520 Models: (1) 600
CPW with no L3 cache and (2) 1200 CPW with L3 cache. With the Accelerator for System i, the 600
CPW can be accelerated to a 3100 CPW system, whereas the 1200 CPW can be accelerated to 3800
CPW.
Trade JDBC Throughput
350
300
250
200
150
100
50
0
500 600 1000 1200 2400 3100 3300 3800
Figure 6.5 - Accelerator for System i
performance data - Capacity comparison
(WAS 6.0 running Trade 6).
IBM i 6.1 Performance Capabilities Reference - January/April/October 2008
©
Copyright IBM Corp. 2008
CPW Rating
cache to a system with L3 cache may scale better than CPW
ratings would indicate.
Chapter 6 - Web Server and WebSphere
In order to showcase the abilities of these
systems, experiments were completed on
WAS 6.0 running Trade 6 to display the
benefits. The following information
describes the models in the context of both
capacity and response time. Results were
collected on System i Model 520 with
varying feature codes depending on the
presence of the Accelerator for System i.
With regards to capacity, Figure 6.5 shows
the 600 CPW model accelerated to 3100
Accelerator CPW increases capacity 5.5 times.
New Models
Additionally, the 1200 CPW model
Old Models
accelerated to 3800 CPW increases capacity
3 times. This provides an extraordinary
benefit when running WebSphere
Applications.
It is also important to note the benefits of
L3 cache. For example, the 1200 CPW
model has 2.5 times more capacity than that
of the 600 CPW system. Additionally, Java
workloads tend to perform better with L3
cache. Thus, besides the benefit of increased
capacity, a move from a system with no L3
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