>>>>> "LRA" == Leonardo Rochael Almeida <[EMAIL PROTECTED]> writes:
LRA> The last two installations belong to the same client, and are LRA> both experiencing a problem that I believe is related to ZEO LRA> latency. Both sites depend heavily on a single ZCatalog for LRA> operation (one ZCatalog hit in almost every page, with some LRA> pages with more than one ZCatalog hit). When site content is LRA> being managed, we're hitting ReadConflict errors (They read LRA> like this: ZODB.POSException.ReadConflictError on database read LRA> conflict error (oid000000000004c0a4, class LRA> BTrees.OOBTree.OOBucket)). The reference to BTrees makes me LRA> think this is ZCatalog related, we don't use BTrees ourselves LRA> anywhere else and we only use regular Folders as bases for our LRA> folderish objects, and managing content causes the reindexing LRA> of objects. Which I think is what is triggering the conflict LRA> errors. Your analysis sounds correct. A read conflict occurs when on thread modifies an object while another thread is reading it (subject to certain other conditions that probably aren't relevant). I assume several users are managing content at the same time. If Zope gets a read conflict, it will retry the transaction. So you must get very unlikely in order to see the error. Each time the transaction is retried, something must go wrong. Are there a lot of concurrent transactions? Or do the updates affect a large number of objects at once? If either is true, it seems like it would make the problem more likely to occur. Jeremy _______________________________________________ Zope-Dev maillist - [EMAIL PROTECTED] http://lists.zope.org/mailman/listinfo/zope-dev ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope )