-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Jonathan wrote:
During recent load testing of a new application 3.1% to 7.6% of all http requests resulted in conflict errors (3.1% with 10 simultaneous users; 7.6% with 50 simultaneous users).
The conflict error occurs when the application attempts to write a small image object into a temporary folder, and each conflict error generates the same traceback:
Traceback (innermost last): Module Zope2.App.startup, line 173, in zpublisher_exception_hook Module ZPublisher.Publish, line 121, in publish Module Zope2.App.startup, line 240, in commit Module transaction._manager, line 96, in commit Module transaction._transaction, line 380, in commit Module transaction._transaction, line 378, in commit Module transaction._transaction, line 433, in _commitResources Module ZODB.Connection, line 484, in commit Module ZODB.Connection, line 518, in _commit ConflictError: database conflict error (oid 0x07, class Products.TemporaryFolder.TemporaryFolder.SimpleTemporaryContainer)
I am running Zope 2.9.2 on CentOS 4.3 (linux).
Does anyone have any ideas as to what I could do to reduce/eliminate these conflict errors?
First, make sure that your application is not trying to overwrite the *same* image in each request. If it needs to do that, then the conflicts are unavoidable. Next, making simultaneous writes into any naive container is going to cause conflicts. You need to think carefully about how you want those writes to work, and plan to minimize conflicts: - Use a BTreeFolder, rather than a normal OFS.Folder (or derivative). - Arrange for the IDs of your images to be substantially different, typically by mangling in a random number (or, for instance, the microseconds value of the current timestamp). Tres. - -- =================================================================== Tres Seaver +1 202-558-7113 tseaver@palladion.com Palladion Software "Excellence by Design" http://palladion.com -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2.2 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFEo+/U+gerLs4ltQ4RAhsUAKCaZIJKLKOcO/X6wkAUo8x83vx3eQCfY5hW /2SHvahGxJ3DSpg4qMlL4D4= =17k2 -----END PGP SIGNATURE-----