Robert Ramey wrote:
I'm wondering if a better name might be something like
transaction process library
or?
rather than persistence library.
IIUC, MVCC can be used to structure complex multithreaded applications, like Postgres or Oracle (http://en.wikipedia.org/wiki/Multiversion_concurrency_control#Databases_with...). It also seems to me that Clojure uses similar approach as a general way to do multithreading (http://clojure.org/concurrent_programming) also there it is called Software Transactional Memory (http://clojure.org/refs). While other aspects of the library, like automatic loading and unloading of objects, maybe of interest to potential users, the multithreaded aspect seems to be very interesting and may be of great demand as the number of CPU cores per machine is increasing. By the way the Wikipedia article on STM (http://en.wikipedia.org/wiki/Software_transactional_memory) has a reference to a library that already implements STM for C++ and is aiming to become part of Boost: http://eces.colorado.edu/~gottschl/tboostSTM/index.html In any case it would be interesting to look at the library code or at least at the documentation. I was thinking about writing something similar several years ago but came to a conclusion that in order to make a rather efficient implementation the library will need to track all reads and writes on the shared object fields. As C++ does not have reflection the user will have to describe shared objects in a very special manner (like wraping all field types in some library provided wrappers) in order for the library to be able to track all the operations. But you seems to solve this issue somehow. How do you track that a balance field is modified? And how do you know which account objects were modified in a given transaction? And it is interesting to know what level of isolation the library provides or is supposed to provide. IIUC, if it aims at serializable isolation level then you are actually providing an STM solution. But if your isolation level is lower (or is changeable) then your library may have different field of application than an STM providing one. Ilya Bobir