[ZODB-Dev] Blobs without shared-blob directory
Hi. I have a configuration with one ZEO database server (ZODB 3.8.1) and two physical servers housing four single-threaded ZEO clients each. There's some 15gb of blob data in the (Plone) site. Setting up and maintaining NFS to share direct access to the blob data is beyond what I can support in production right now. So this leaves me with a blob-cache per ZEO client. Am I correct to assume that sharing the blob-cache between the four processes on the same physical machine is not supported, as these don't have any mechanism to synchronize read/write activity to the blob-cache? Or is there something in the blob design that ensures a no-conflict situation? Does the blob-cache grow indefinitely or is there some mechanism to purge / pack it built-in somewhere? Thanks, Hanno ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] Blobs without shared-blob directory
On May 15, 2009, at 6:22 AM, Hanno Schlichting wrote: Hi. I have a configuration with one ZEO database server (ZODB 3.8.1) and two physical servers housing four single-threaded ZEO clients each. There's some 15gb of blob data in the (Plone) site. Setting up and maintaining NFS to share direct access to the blob data is beyond what I can support in production right now. So this leaves me with a blob-cache per ZEO client. Am I correct to assume that sharing the blob-cache between the four processes on the same physical machine is not supported, as these don't have any mechanism to synchronize read/write activity to the blob- cache? Or is there something in the blob design that ensures a no-conflict situation? It probably works in ZODB 3.8, although there are no tests for it. I made sure it works in 3.9 and there are tests for it. This is our (ZC's) production configuration. Does the blob-cache grow indefinitely or is there some mechanism to purge / pack it built-in somewhere? ZODB 3.9 has an option to limit the blob cache size. We're using that too. Note that the ZODB 3.9 blob cache uses it's own layout to facilitate the management of the cache. You can't use a 3.8 blob cache with 3.9. Jim -- Jim Fulton Zope Corporation ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] Blobs without shared-blob directory
Jim Fulton wrote: On May 15, 2009, at 6:22 AM, Hanno Schlichting wrote: Am I correct to assume that sharing the blob-cache between the four processes on the same physical machine is not supported, as these don't have any mechanism to synchronize read/write activity to the blob- cache? Or is there something in the blob design that ensures a no-conflict situation? It probably works in ZODB 3.8, although there are no tests for it. I made sure it works in 3.9 and there are tests for it. This is our (ZC's) production configuration. Ok, I'll not try it for now on a tight deadline, but will consider it for more quiet times. Unfortunately 3.9 and Zope 2.10 don't quite want to work with each other. Does the blob-cache grow indefinitely or is there some mechanism to purge / pack it built-in somewhere? ZODB 3.9 has an option to limit the blob cache size. We're using that too. Note that the ZODB 3.9 blob cache uses it's own layout to facilitate the management of the cache. You can't use a 3.8 blob cache with 3.9. Ok, thanks! I'll live with some outside cronjob driven purging for now. Hanno ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
