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Sun Java System Application Server Enterprise Edition 8.2 Performance Tuning Guide

Configuring Grizzly

Grizzly is an HTTP Listener using Java's NIO technology and implemented entirely in Java. This re-usable, NIO–based framework can be used for any HTTP related operations (HTTP Listener/Connector) as well as non-HTTP operations, thus allowing the creation of any type of scalable multi-threaded server. The Grizzly HTTP Listener uses a keep-alive system based on the NIO Selector classes of the Java platform, which support connection monitoring and help prevent Denial-of-Service attacks. The Denial–of–Service systems will add basic support for IP validation, number of transactions completed per IP, detection of inactive connections, etc. in order to predict resource exhaustion or "flooding" attacks. All these services are performed in conjunction with the Keep-Alive systems. The Grizzly connector will forward requests for both static and dynamic resources to the servlet container, which processes requests for static resources via a dedicated, container-provided servlet (org.apache.catalina.servlets.DefaultServlet).

For more information about Grizzly, you can read the weblog at http://weblogs.java.net/blog/jfarcand/archive/2005/06/grizzly_an_http.html

Grizzly is available as a replacement to NSAPI/WebCore in Application Server Enterprise Edition8.2. Application Server provides some special properties to support the configuration of Grizzly. To enable Grizzly, add the following property:

Dcom.sun.enterprise.web.httpservice.ee=false.

Currently, the implementation of Grizzly supports all the Application Server Enterprise Edition functionality, except dynamic configuration.

The following properties control the Grizzly configuration:

Note –

Like all Sun Java System Application Server 8.2 configurations, Grizzly also performs better when the Asynch Startup mechanism is disabled. You can disable it using this property: -Dcom.sun.enterprise.server.ss.ASQuickStartup=false

The following table brings out the corresponding properties of Grizzly and the production web container (PWC).

Table 3–3 Correspondence of Grizzly and PWC Properties

Property Name in Grizzly 

Default Value 

Description 

Corresponding setting in a production web container 

maxAcceptWorkerThread 

0 

Number of threads used to serve OP_ACCEPT (socket.accept()). 

acceptor threads in http listener 

selector.timeout 

60000 

Time in milliseconds before Selector.select() times out. 

request processing timeout 

minWorkerThreads 

5 

The minimum number of threads every thread pool uses at creation.  

request processing initial thread count 

fileCache.isEnabled 

false 

Indicates if file caching is enabled. 

file cache enabled 

fileCache.minEntrySize 

 

Minimum size that a small file can have. 

small file size limit 

fileCache.maxEntrySize 

1024 

Maximum size that a medium file can have. 

medium file size limit 

fileCache.maxLargeFileCacheSize 

10485760 

Cache space for medium files. 

medium file size 

fileCache.maxSmallFileCacheSize 

 

Cache space for small files.  

small file size 

fileCache.maxCacheEntries 

 

Maximum number of cached entries.  

max files count 

keepAliveTimeoutInSeconds 

30 

 

keep alive timeout 

maxKeepAliveRequests 

250 

 

keep alive max connections 

InitialRuleCount 

128 

The initial number of KeepAliveRule created by the Keep-Alive subsystem. 

 

useNioNonBlocking 

true 

Indicates whether to use NIO blocking mode or not. 

 

displayConfiguration 

false 

Display Grizzly internal configuration. 

 

useDirectByteBuffer 

true 

Indicates if ByteBuffer.allocateDirect() is used when creating Grizzly buffers. 

 

pipelineClass 

com.sun.enterprise.web.connector.grizzly.LinkedListPipeline 

The default Pipeline (Thread Pool wrapper) used by Grizzly. 

 

maxSelectorReadThread 

1 

The number of selector threads for handing OP_READ operations. 

 

useByteBufferView 

false 

Specifies whether to use a large ByteBuffer and slice it amongst Grizzly buffers. 

 

algorithmClassName 

com.sun.enterprise.web.connector.grizzly.algorithms.NoParsingAlgorithm 

The request bytes parsing algorithm used to read bytes from ByteBuffer. 

 

buffersize 

4096 

ByteBuffer size created by Grizzly. 

 

factoryTimeout 

30 

Time taken before a read/write operation fails on a socket. 

 

maxReadWorkerThread 

0 

Number of threads used to read the request bytes from the socket.