[Zodb-checkins] CVS: ZEO - CHANGES.txt:1.28.2.1 README.txt:1.1.4.2

[Jeremy Hylton]

Update of /cvs-repository/ZEO
In directory cvs.zope.org:/tmp/cvs-serv31901

Modified Files:
      Tag: ZEO2-branch
	README.txt 
Added Files:
      Tag: ZEO2-branch
	CHANGES.txt 
Log Message:
Emphasize protocol incompatibility in README.txt.

Add CHANGES.txt with brief overview of 2.0 and 1.0 differences.



=== Added File ZEO/CHANGES.txt ===
Revision History, Zope Enterprise Objects, version 2

  ZEO 2.0 alpha 1

    Brief overview of the differences between ZEO 1.0 and 2.0.
      
      - New protocol.

        ZEO 2 uses a different wire protocol and a different API to
        make RPC calls.  The new protocol was designed to be flexible
        and simple.  It includes an initial handshake to set the 
        version number, which should allow future changes to the
        protocol while reducing the difficulty of upgrades.

      - Better handling of concurrent commits.

        The ZEO server serializes concurrent commits to guarantee
        consistency; the mechanism is often called the distributed
        commit lock.  ZEO 2 improves the efficiency of concurrent
        commits by allowing data to be transferred to the server
        before entering the commit lock.

      - The ZEO client and server can be configured to operate in
        read-only mode.

      - A ZEO client can be configured with multiple server addresses.
        It uses the first server it can connect to.

      - The wait_for_server_on_startup keyword argument to
        ClientStorage has been renamed wait.



=== ZEO/README.txt 1.1.4.1 => 1.1.4.2 ===
   information, see the ZEO Web page at http://www.zope.org/Products/ZEO/.
 
-  ZEO version 2 is not backwards compatible with ZEO 1.0.  A system
-  that uses ZEO must upgrade all clients and the same time it upgrades
-  the server.
+  IMPORTANT: ZEO version 2 is not backwards compatible with ZEO 1.0.
+  A system that uses ZEO must upgrade all clients and the same time it
+  upgrades the server.
 
   The ZEO package is contained in the directory named ZEO.