Posted by Coder.
Results > Posts Filed Under > Patterns
Jul
18
Posted by Coder.
Hadoop Summit 2010 – Agenda
Hadoop is a powerful platform for data analysis and processing, but many struggle to understand how it fits in with regard to existing infrastructure and systems. A series of common integration points, technologies, and patterns are defined and illustrated in this presentation. [slides]
Mar
11
Posted by Coder.
Performance Anti-Patterns
Update: Follow-up Discussion on Artima
What and how should we be measuring? A good benchmark is:
Repeatable, so experiments of comparison can be conducted relatively easily and with a reasonable degree of precision.
Observable, so if poor performance is seen, the developer has a place to start looking. Nothing is more frustrating than a complex benchmark that delivers a single number, leaving the developer with no additional information as to where the problem might lie.
Portable, so that comparisons are possible with your …
Feb
27
Posted by Coder.
Embedded.com – Using design patterns to identify and partition RTOS tasks: Part 1
… any operation whose deadline is measured in milliseconds—not microseconds—is a candidate for a high priority task. Assuming that your system has some serious computing to do at least once in a while, then anything that your system must do in milliseconds will miss its deadline if it has to wait for the serious computing to complete. (If your system never has any time-consuming CPU activity, then you’re …
Feb
10
Posted by coder.
Sun Dialogue Programs
(Q): If you have to pick top 10 things that you must monitor on any server to look for performance and/or scalability issues…what would they be?
Richard McDougall (A): Off the top of my head, in no particular order:
CPU: Check idle time and run queue length.
If there’s a CPU bottleneck, check if it’s an application or kernel CPU utilization issue with mpstat: high percentages of users indicate it’s an application issue. High sys may point to high network load …
Jul
27
Posted by Coder.
Asked “What is Refactoring?” Martin Fowler answers “Refactoring is a disciplined technique for restructuring an existing body of code, altering its internal structure without changing its external behavior.”
Cyrus Najmabadi (developer at Microsoft) writes on his blog Cyrus’ Blather, “… if you perform an “extract method” of some code that sits in a tight loop, and that the jit doesn’t inline, then you’ll have changed the external behavior with respect to its performance. However, there’s no good way …