Extremely slow OAI metadata retrieval through Dublin Core

[CDTux]

(OJS version 3.1.2.0)

Upon validating OAI-PMH data on http://validator.oaipmh.com/ with http://historiaregional.org/ojs/index.php/historiaregional/oai (the journal in question), though ListRecords for OAI_MARC, MARCXML and RFC1807 work correctly, OAI_DC provides no response at all, as if it had timed out.

Indeed, when checking directly with http://historiaregional.org/ojs/index.php/historiaregional/oai?verb=ListRecords&metadataPrefix=oai_dc it takes several minutes for the site to provide the XML data.

What could be causing the delay for this Dublin Core format in particular?

[Enrique_Manuel_Touce]

Hi, we have the same problem and the problem was on mysql with this two changes resolve it

innodb_flush_log_at_trx_commit = 2

and change mysql tmp directory into ram

[CDTux]

Better late than never, what we ended up doing was changing oai_max_records in config.inc.php to a value of 1. Hardly a convenient solution, but when the server is working correctly the response time is decent. (2.3 s) Even a slightly higher number ended with problematic response times. This change to 1 was enough for OAI-PMH to consider the journal compliant.

We would have liked to try Enrique_Manuel_Touce’s solution, but unfortunately our hosting company did not give us permission to implement that change.

[asmecher]

Hi @CDTux,

Glad you found a work-around, but I suspect the poor performance of the OAI interface is caused by some underlying database problem like a missing index or some tables using a different MySQL storage than the others (MyISAM vs. InnoDB). I suspect resolving that database problem will allow you to easily turn your oai_max_records back up to the default, and will probably improve performance elsewhere in the system.

Regards,
Alec Smecher
Public Knowledge Project Team