Log message for revision 113141: Fill in the what's new section for the ZODB
Changed: U Zope/trunk/doc/WHATSNEW.rst -=- Modified: Zope/trunk/doc/WHATSNEW.rst =================================================================== --- Zope/trunk/doc/WHATSNEW.rst 2010-06-05 13:35:54 UTC (rev 113140) +++ Zope/trunk/doc/WHATSNEW.rst 2010-06-05 14:11:29 UTC (rev 113141) @@ -11,9 +11,49 @@ ZODB 3.10 --------- -... +This version of Zope includes ZODB 3.10 - a new major version of the ZODB. +Among the notable changes are a variety of performance improvements. The ZEO +server process is now multi-threaded. If the underlying file system and disk +storage can handle concurrent disk I/O efficiently a throughput increase by a +factor of up to four has been seen. On a related note using solid state disks +for the ZEO server has a similar effect and can increase throughput by the +same factor. Both of these effects combined can lead to an increase of up to +sixteen times the throughput in high load scenarios. +File storage indexes use a new format, which is both smaller in size and can +be read much faster. The repozo backup script now also backs up the index files +in addition to the actual data, so in a restore scenario the index doesn't have +to be recreated. For large databases this can bring down the total downtime in +a restore scenario by a significant amount of time. +The ZODB has added support for wrapper storages that transform pickle data. +Applications for this include compression and encryption. A storage using +standard zlib compression is available as a new package called +`zc.zlibstorage <http://pypi.python.org/pypi/zc.zlibstorage>`_. In content +management scenarios where strings constitute the most of the non-blob data, +this can reduce the Data.fs size by a factor of two or more. The overhead of +compressing and uncompressing is negligible. This saves both network I/O and +disk space. More importantly the database has better chances of fitting into +the operating systems disk cache and thus into memory. The second advantage is +less important when using solid state disks. + +Databases now warn when committing very large records (> 16MB). This is to try +to warn people of likely design mistakes. There is a new option +(large_record_size/large-record-size) to control the record size at which the +warning is issued. This should help developers to better understand the storage +implications of their code, which has been rather transparent so far. + +The mkzeoinst script has been moved to a separate project +`zope.mkzeoinstance <http://pypi.python.org/pypi/zope.mkzeoinstance>`_ and is +no-longer included with ZODB. You will need to use this new package to set up +ZEO servers or use the +`plone.recipe.zeoserver <http://pypi.python.org/pypi/plone.recipe.zeoserver>`_ +recipe if you use `buildout <http://www.buildout.org/>`_. + +More information can be found in the detailed +`change log <http://pypi.python.org/pypi/ZODB3/3.10.0b1.>`_. + + WSGI ---- _______________________________________________ Zope-Checkins maillist - Zope-Checkins@zope.org https://mail.zope.org/mailman/listinfo/zope-checkins