Hi all, We are running DSpace 5.9 XMLUI with Tomcat 7 and Java 8 on a RHEL 7 server, with a small-ish collection of items (about 20,000). We are running production with Oracle 12, but I have replicated the same issue with Postgresql 9.2.
We have recently noticed some very long page load times. Any given discover/search page can take 2-7 seconds to load, and when there is even a moderate amount of traffic (e.g., when a bot is indexing the site at about 10 requests per second), page load times can take 30-60 seconds or longer. We have made the changes suggested at https://wiki.duraspace.org/display/DSDOC5x/Performance+Tuning+DSpace for both Tomcat and PostgreSQL. Our production site has been customized extensively, but I was able to replicate the issue with an untouched DSpace 5.9 build using the default Mirage theme with XMLUI. The issue is the same with both Oracle and PostgreSQL (PostgreSQL seems a little bit better). I have tried changing from Java 8 to Java 7. I have bumped up the database connection pool size to 300. Digging through the logs is difficult, since the problem only really emerges under (moderate) load. However, I was able to track a single page request (to /discover), and noticed that there were over 9000 individual SQL queries (for a single page load) that looked like: DEBUG org.dspace.storage.rdbms.DatabaseManager @ Running query "SELECT * FROM MetadataValue WHERE resource_id= ? and resource_type_id = ? ORDER BY metadata_field_id, place" with parameters: 144458,0 (The resource_type_id `0` is for bitstreams.) I *think* (but could be wrong) that this is the source of our performance problem; that the database is just getting bogged down with so many requests. Looking at PostgreSQL's slow query logging, some of these individual queries are taking about 1 second. Our situation is perhaps unique in that we have dozens (sometimes hundreds) of "dark" (non-ORIGINAL) archival files associated with an item, and it looks like this discover page is trying to load metadata for all of them. This doesn't happen with an equivalent query in JSPUI. Any suggestions or workarounds? Why does the search page need to get metadata for all bitstreams? Does anyone know if upgrading to DSpace 6 would resolve this issue? Thanks, Jacob -- All messages to this mailing list should adhere to the DuraSpace Code of Conduct: https://duraspace.org/about/policies/code-of-conduct/ --- You received this message because you are subscribed to the Google Groups "DSpace Technical Support" group. To unsubscribe from this group and stop receiving emails from it, send an email to dspace-tech+unsubscr...@googlegroups.com. To post to this group, send email to dspace-tech@googlegroups.com. Visit this group at https://groups.google.com/group/dspace-tech. For more options, visit https://groups.google.com/d/optout.
