For those who asked... Our objective was to determine the fastest way to upload a large number of records into a zcatalog. The test data to be uploaded consisted of 832,923 records and required 2.9G of disk space (for the input data files). Each input data record will become a single zclass instance and a single entry in the zcatalog. ZClass instances are being stored in a BTreeFolder2 folder. The update process is split into 120 update batches. The update batches vary in size from 244 records to 24,360 records. Approach #1 - External Method In this approach a standard zope external method is used to read the input data files, create zclass instances and update the zcatalog. The zclass instance is 'catalog-aware', therefore the zcatalog is automatically updated when the zclass instance is created. After the field data is added to the zclass instance, a second update of the zcatalog (done via reindex_object) is required to cause the additional fields to become indexed. The total time required to process the 120 update batches was 400,438 seconds. This does not include time to pack the zodb, which occured automatically after every 10 update batches. Approach #2 - Direct to zodb In this approach a stand-alone python routine was used to access the DBData.fs file (mounted via DBTab) directly (ie. zope is not running during the update process). The ZClass instances in this approach are NOT 'catalog-aware' (ie. catalog_object was called after the ZClass instance was created and the field data added - the reason was to eliminate the initial automatic zcatalog update). The total time required to process the 120 update batches was 270,903 seconds. This represents a time savings of 32.35%, additionally the automated zodb pack process appears to run faster than in Approach #1 (the longest pack time in Approach #2 was about 2.5 hours vs over 4 hours in Approach #1). Here are the specs on the server dedicated to the updates (same server used for both tests) Zope 2.6.1 Python 2.1.3 Linux 2.4.20-28.8 (Red Hat 8.0 3.2-7) Processor 1Ghz (VIA - PIII clone, 64k cache, 1998.84 bogomips) Ram 1.25G Disk: RAID 1 (3 spindles, 5ms, 10000rpm) Jonathan