This chapter describes changes, enhancements, and corrections made to the Oracle Coherence documentation for 12c (12.1.2).
The Coherence documentation for 12c (12.1.2) can be found at the following URL:
http://docs.oracle.com/middleware/1212/coherence/index.html
This chapter contains the following sections:
Coherence*Extend 12c (12.1.2) Backward Compatibility Exception
Incorrect Default Value for coherence-session-thread-locking Parameter
Incorrect Information Regarding Sticky Sessions and Locking for Coherence*Web
Text for Coherence*Extend Version Compatibility has been Revised
Incorrect listing for session-cache-config.xml File Without a Near Cache
New Performance Report for Coherence*Web in WebLogic Server Environments
An SSL socket provider can be configured to control the use of potentially weak ciphers or specific protocol versions.
To control cipher suite and protocol version usage, edit the SSL socket provider definition and include the <cipher-suites> element and the <protocol-versions> elements, respectively, and enter a list of cipher suites and protocol versions using the name element. Include the usage attribute to specify whether the cipher suites and protocol versions are allowed (value of white-list) or disallowed (value of black-list). The default value for the usage attribute if no value is specified is white-list. For example:
<socket-provider>
<ssl>
...
<cipher-suites usage="black-list">
<name>TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256</name>
</cipher-suites>
<protocol-versions usage="black-list">
<name>SSLv3</name>
</protocol-versions>
...
</ssl>
</socket-provider>
Coherence 12.1.2.x cluster proxies are backward compatible with extend clients versions 3.x. That is, 3.x clients can connect to 12.1.2.x cluster proxies. Backward compatibility in 12.1.2.x is an exception to the Coherence*Extend version compatibility policy. Cluster proxies beyond version 12.1.2 may not include the current exception and may not maintain backward compatibility.
The Coherence .NET version number has been changed to support the .NET version convention that supports only up to 4 digits (N.N.N.N). Because Oracle version numbers use 5 digits (N.N.N.N.N), the 4th and 5th Oracle digits are combined for the 4th .NET version digit. For details on the mapping, see "Coherence .NET Version Number Mapping" in Oracle Fusion Middleware Developing Remote Clients for Oracle Coherence.
The default near cache invalidation strategy auto has changed to ensure that reduced network traffic is prioritized over performance. Set the invalidation strategy to all for pre-12c (12.1.2) default behavior.
Deploying a GAR file as a shared library requires additional steps over regular shared library deployment. For more information, see "Deploying Coherence Applications as Shared Libraries" in Developing Oracle Coherence Applications for Oracle WebLogic Server.
You can use Portable Object Format (POF) serialization with Oracle Coherence GoldenGate HotCache (HotCache). POF is a language-agnostic binary format. POF was designed to be very efficient in both space and time and has become a cornerstone element in working with Coherence. For more information, see "Using Portable Object Format with HotCache" in Oracle Fusion Middleware Integrating Oracle Coherence.
In addition to "Integrating Hibernate and Coherence" in Oracle Fusion Middleware Integrating Oracle Coherence, you can find information on integrating Coherence with Hibernate in the Coherence Community projects at the following URL:
Documentation for Spring support has been moved from the Coherence 12c (12.1.2) product distribution to the Coherence Community projects. It is no longer described in the Oracle Fusion Middleware Integrating Oracle Coherence documentation. For information on integrating Oracle Coherence with Spring, see the following URL:
The description of the coherence-session-thread-locking parameter in the "Coherence*Web Context Parameters" appendix in Administering HTTP Session Management with Oracle Coherence*Web incorrectly lists the default value as true. The correct default value should be false.
The "Troubleshooting Locking in HTTP Sessions" section in Oracle Fusion Middleware Administering HTTP Session Management with Oracle Coherence*Web indicates:
"Enabling Member, Application, or Thread Locking for HTTP session access indicates that Coherence*Web will acquire a clusterwide lock for every HTTP request that requires access to a session. The exception to this is when sticky load balancing is available and the Coherence*Web sticky session optimization is enabled."
The sentence "The exception to this is when sticky load balancing is available and the Coherence*Web sticky session optimization is enabled." has been removed in the current version of the book because it is confusing. Even if sticky sessions are enabled, Coherence*Web will still hold a clusterwide lock for a session—it simply will not release it after the request has finished.
The text describing compatibility between Coherence*Extend versions has been revised. Here is the new text:
Compatibility for the extend protocol and POF is maintained between point releases (for example, 1.0, 1.1, and so on) but may not be maintained between major releases (for example, 1.0, 2.0, and so on).
Note:
Compatibility requires the use of POF, because POF can support backward compatible serialization change.Prior to version 12.1.2.0.1, extend clients only support forward compatibility with cluster proxies. That is, extend clients can connect to cluster proxies that have either the same or higher version numbers (within a major release).
Starting with version 12.1.2.0.1, extend clients support both forward and backward compatibility with cluster proxies. That is, extend clients can connect to cluster proxies that have lower or higher version numbers (within a major release). For example, a 12.1.3 extend client can connect to a 12.1.2.0.1 proxy. Extend client backward compatibility is not supported on proxy versions 3.7.1 or earlier.
Coherence 12.1.2 Backward Compatibility Exception
Coherence 12.1.2 cluster proxies are backward compatible with version 3 extend clients (3.3, 3.4, 3.5, 3.6, and 3.7). That is, version 3 clients can connect to 12.1.2 cluster proxies. Backward compatibility in 12.1.2 is an exception to the Coherence*Extend major release compatibility policy that is described above. Cluster proxies beyond version 12.1.2 may not include the current exception and may not maintain backward compatibility.
There was an error in the listing for a sample session-cache-config.xml file without a near cache that appeared in "Session Cache Configuration File Without a Near Cache" appendix of Oracle Fusion Middleware Administering HTTP Session Management with Oracle Coherence*Web. See the new listing in the "Session Cache Configuration File Without a Near Cache" appendix.
Available since Coherence 12.1.2.0.3. The Weblogic Web Report (report-web-weblogic.xml) provides information on Coherence*Web activity when it is being used in WebLogic Server environments. This report provides the same information as provided by the Web Report (see "Web Report" in Oracle Fusion Middleware Administering HTTP Session Management with Oracle Coherence*Web), with additional columns for the WebLogic Server name and domain name. The report is a tab-delimited file that is prefixed with the date and hour in YYYYMMDDHH format and appended with -web-weblogic.txt. For example 2009013102-web-weblogic.txt would be created on January 1, 2009 at 2:00 am.
Table 2-1 Contents of the WebLogic Web Report
| Column | Data Type | Description |
|---|---|---|
|
|
String |
The application name. |
|
|
long |
A sequential counter to help integrate information between related files. This value does reset when the Reporter restarts and is not consistent across nodes. However, it is helpful when trying to integrate files. |
|
|
long |
The number of overflow updates since the last time the report was created. |
|
|
long |
The number of session updates since the last time the report was created. |
|
|
String |
The name of the WebLogic Server domain in which Coherence*Web is running. |
|
|
long |
The attribute count on the node. |
|
|
long |
The session count on the node. |
|
|
integer |
The node identifier. |
|
|
float |
The average size for attribute overflows. |
|
|
long |
The maximum size for an attribute overflow. |
|
|
long |
The total number of attribute overflow updates since the last time statistics were reset. |
|
|
Date |
The system time when the report was created. |
|
|
String |
The name of the WebLogic Server on which Coherence*Web is running. |
|
|
float |
The average number of seconds a session is active. |
|
|
float |
The average size for a session. |
|
|
long |
The maximum size for a session. |
|
|
long |
The minimum size for a session. |
|
|
long |
The number of sticky sessions on the node. |
|
|
long |
The number of session updates since the last time statistics were reset. |