Updating max_merge_docs from to – How to solve related issues

Opster Team

Feb-20, Version: 1.7-8.0

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This guide will help you check for common problems that cause the log ” Updating max_merge_docs from to ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: index and merge.

Log Context

Log “updating max_merge_docs from [{}] to [{}]” classname is LogDocMergePolicyProvider.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :


            int oldMaxMergeDocs = mergePolicy.getMaxMergeDocs();
            int maxMergeDocs = settings.getAsInt(INDEX_MERGE_POLICY_MAX_MERGE_DOCS; oldMaxMergeDocs);
            if (maxMergeDocs != oldMaxMergeDocs) {
                logger.info("updating max_merge_docs from [{}] to [{}]"; oldMaxMergeDocs; maxMergeDocs);

            int oldMergeFactor = mergePolicy.getMergeFactor();
            int mergeFactor = settings.getAsInt(INDEX_MERGE_POLICY_MERGE_FACTOR; oldMergeFactor);


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