Use the Java concurrency API to speed up time-consuming tasks
New Oracle10g SQL optimizer hints
With each new release of Oracle, there are more tuning controls and opportunities for improving the execution speed of SQL. In an article about speeding up SQL execution in Oracle, I discussed some common SQL tuning hints and, in another article, I warned about performance issues when using SQL hints inside views.
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Oracle tuning with hints has always been complex, and the Oracle Technical Network has a great overview into the processes of using hints to tune Oracle SQL. With the introduction of 10g database, there are many new optimizer hints available to control the optimizer behavior. Let’s take a quick tour of these powerful new hints:
Hibernate Performance Tips（Hibernate 性能技巧）
Some people I know are looking at porting their (very large) J2EE application from using a homegrown OR framework on top of Entity Beans with CMP (without CMR) to Hibernate, and they asked me for some tips. I‘m not claiming to be a Hibernate expert, but I‘ve used it on an enterprise product, added features, submitted patches, etc. so I know a bit. Since I was writing this up anyway, I figured I‘d blog it.
Search-Enable Your Application with Lucene
By: Craig Walls
The e-commerce Web site that I work on has seen several incarnations of its search feature. We started with plain vanilla SQL using "like" clauses, but this didn't perform well and left a lot to be desired in language features such as stemming (e.g., "paint" = "painter" = "painting") and synonym matching (e.g., "cat" = "feline"). Next we tried an off-the-shelf solution. This addressed our efficiency and language demands, but it was ridden with strange quirks and we were limited in how much we could customize its behavior.
Then we discovered Lucene. Lucene is an open-source search framework from Apache's Jakarta project. As a framework, Lucene provides you with the building blocks you need to build a search engine that meets your specific searching requirements. Lucene is flexible, fully customizable, and amazingly fast.
Frequently Asked Questions About the Java HotSpot VM
The questions and answers are divided into the following topics.
The Java HotSpot VM Architecture and Use
Scaling Enterprise Java on 64-bit Multi-Core X86-Based Servers
Multi-core and 64-bit CPUs are the hottest commodities in the enterprise server market these days. In recent years, as the cost and power requirement of faster CPU clock speeds has increased, the growth in raw clock speed (usually measured in megahertz) of single CPUs has slowed down. Hardware manufacturers continue to improve X86-based server performance by increasing both the multitasking capability and internal data bandwidth. Both Intel and Advanced Micro Devices are shipping 64-bit processors with two internal CPU cores, and quad core processors are soon to follow. Ninth-generation servers from Dell exploit this new generation of chips. The PowerEdge 1955 blade server, for example, supports up to two 64-bit dual core processors in a blade configuration, with up to ten such blades in a 7-rack unit (12.25") chassis.
Creating Images in a Java Servlet
Setting up the Servlet
As with most servlets, this servlet will override the doGet() method in HttpServlet. The doGet() method will be called when an HTTP GET request is made to the servlet. We can expect an HTTP GET request when a servlet is called within an <img> tag.