Log Increase RLIMIT-MEMLOCK; soft limit: – How To Solve Related Issues

Log Increase RLIMIT-MEMLOCK; soft limit: – How To Solve Related Issues

Opster Team

Feb-20, Version: 1.7-8.0

Before you begin reading this guide, we recommend you try running the Elasticsearch Error Check-Up  which can resolve issues causing many log errors (free and no installation required)


This guide will help you check for common problems that cause the log “Increase RLIMIT-MEMLOCK; soft limit:” to appear. It’s important to understand the issues related to the log, so to get started, read the general overview on common issues and tips related to the Elasticsearch concepts: bootstrap.

Advanced users might want to skip right to the common problems section in each concept or try running the Check-Up which analyses ES to discover the cause of many errors and provides suitable actionable recommendations. 

Log Context

Log”Increase RLIMIT_MEMLOCK; soft limit:” classname is JNANatives.java
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

         // mlockall failed for some reason
        logger.warn("Unable to lock JVM Memory: error=" + errno + ";reason=" + errMsg);
        logger.warn("This can result in part of the JVM being swapped out.");
        if (errno == JNACLibrary.ENOMEM) {
            if (rlimitSuccess) {
                logger.warn("Increase RLIMIT_MEMLOCK; soft limit: " + rlimitToString(softLimit) + "; hard limit: " + rlimitToString(hardLimit));
                if (Constants.LINUX) {
                    // give specific instructions for the linux case to make it easy
                    String user = System.getProperty("user.name");
                    logger.warn("These can be adjusted by modifying /etc/security/limits.conf; for example: \n" +
                                "\t# allow user '" + user + "' mlockall\n" +


Related issues to this log

We have gathered selected Q&A from the community and issues from Github, that can help fix related issues please review the following for further information :

1 Unable to lock JVM Memory: error=12, reason=Cannot allocate memory – Elasticsearch 6.2.4 -views 5.38 K ,score 5

Problem Configuring The Memory  


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