I'm using a simple PHP library to add documents to a SOLR index, via HTTP. There are 3 servers involved, currently: The PHP box running the indexing job A database box holding the data being indexed The solr box. At 80 documents/sec (out of 1 million docs), I'm noticing an unusually high interrupt rate on the network interfaces on the PHP and solr boxes (2000/sec; what's more, the graphs are nearl