To understnad ZODB Performance, once needs to understand the structure of ZODB. There are many ways to store the ZODB data. Each one has different performance characteristics. The simplest is file storage. All the data is stoed in one file. Large objects, such as images and documents can be stored in a separate file called a blob. For increased performance, one can use ZEO as a sharred database server, and cache the objects in ZEO server memery or in the application server memory. For even better performance, one can use RelStorage, to store the objects in a relational database, or NEO to store the objects in multiple relational databases.
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