: As far as our application goes, Commits and reads are done to the index : during the normal business hours. However, we observed the max warmers : error happening during a nightly job when the only operation is 4 : parallel threads commits data to index and Optimizes it finally. We : increased the number of warmers from 2 to 4 after seeing the error : getting solved in QA.
i suspect that there is no real problem, just threads colliding with eachother trying to do commits at the same time. if you have 4 threads doing updates, and each thread does a commit when they are done (or when they are done with a "batch") there's a lot of possibility for collision. waiting for all of the threads to finish and then doing a single commit, or executing commits from a fifth thread at a regular interval, (or just using the autocommit settings in solrconfig.xml) should cause the data to be visible just as fast, but without the contention of multiple clients trying to force commits at the same time. -Hoss
