If you’re still looking for a good reason to spend a few minutes tuning your SOLR caches (documentCache, filterCache and queryResultCache), I’ll give you two numbers:

avgTimePerRequest : 126.148822 avgTimePerRequest : 70.026436

The first is with the default cache settings, the latter is with a very small change. Yep. That’s a 45% speed increase. So, the interesting question is what Iactually changed in the cache configuration – although I should warn you, the answer is very, very, very complicated:

This is perhaps the most obvious and “not very helpful” post for quite a few people, but for those who experience this issue, it’ll save the day. While doing a test index routine of around 6 million documents, things would get really slow at the moment I passed 1 million documents in the index. Weird. Optimizing didn’t help, as it died with an exception after a while.

The reason?

Not enough free disk space. Solr was indexing to a different partition than I thought.

Solved everything.

Here’s a small shell script I’m using to submit pre-made XML documents to Solr. The documents are usually produce by some other program, before being submitted to the Solr server. This way we submit all the files in an active directory to the server (here all the files in the documents directory (relative to the location of the script) will be submitted) .

You’ll have to update the URL and the directory (documents) below. We usually group together 1.000 documents in a single file, so the commit happens for every thousand documents. If you use autocommit in Solr, you can remove that line. This script requires CURL to talk to the Solr server.