Java Reference
In-Depth Information
R
EFACTORED
SOLUTION
NAME
:
Workload Management.
S
OLUTION
ALSO
KNOWN
AS
:
Even Load Balancing.
R
EFACTORED
SOLUTION
TYPE
:
Technology.
R
EFACTORED
SOLUTION
DESCRIPTION
:
True load-balancing dispatchers
help. Partitioning larger jobs into smaller ones can even out a workload,
and the specialization of certain servers to handle longer jobs can produce
significant benefits.
T
YPICAL
CAUSES
:
Dynamic content is much more uneven. When the same
primitive techniques are used to balance static and dynamic jobs, uneven
distribution of work can be the result. In addition, if odd long jobs are
treated the same as other jobs, they'll throw off round-robin load-balanc-
ing schemes.
S
YMPTOMS
,
CONSEQUENCES
:
Sporadic performance and inconsistent per-
formance across identically configured servers are the most common
symptoms.
S
OLUTION
ALTERNATIVES
:
Server consolidation to a single high-powered
server eliminates this problem completely, at the price of convenient
scalability.
Chaotic Session State Management
D
ESCRIPTION
:
Certain state management techniques with distributed
architectures have different strengths and weaknesses. Some alternatives
include dispatching with session affinity, distributed state management,
stateful session bean state management, and entity bean state manage-
ment. These techniques can easily be misapplied.
M
OST
FREQUENT
SCALE
:
Enterprise. In many cases, an enterprise imple-
mentation will dictate an approach.
R
EFACTORED
SOLUTION
NAME
:
Correct Choice of Technique.
R
EFACTORED
SOLUTION
TYPE
:
Software.
R
EFACTORED
SOLUTION
DESCRIPTION
:
Choose the right tool for the job.
Understand the problem domain and the technologies that will be applied
to the problem.
R
OOT
CAUSES
:
Ignorance.
S
YMPTOMS
,
CONSEQUENCES
:
Improper choice of technique can result in
poor performance, difficult application maintenance, and difficult
extensibility.