[Erp5-dev] Major upgrade to ZSQLCatalog

[Jean-Paul Smets]

Hi,

I have commited a major upgrade to ZSQLCatalog. This upgrade solves the 
second part of locking issues: uid generation. By generating uid values in 
advance and allocating a list of 1000 uids stored in RAM to each thread, 
object creation ERP5 does not require any call to ZSQLCatalog. 

This approach is compatible with a highly distributed ZEO environment.

This tremendously not only reduces the risks of locks (which had already 
nearly disappeared BTW with the 3 phase transaction system in CMFActivity), 
but also accelerated data input. Creating a new document now takes less 
than 100ms on my laptop.

The main consequence of this upgrade are:
	- requirement to add 2 methods to portal_catalog 
(z_produce_reserved_uid_list and z_clear_reserved)
	- make sure the 2 methods are selected in portal_catalog properties
	- replace z0_catalog_object by z_update_object in catalog properties 
(z0_catalog_object  is no longer useful since catalog lines are always 
pre-allocated by uid generator)

The 'advanced' menu in the catalog has a new section for clearing reserved 
uids.

I could successfully pas unit tests for category with this new catalog. 
However, more testing is still required.

JPS.