Explicitly set Elasticsearch heap size during CI and local development (#86513) (#86573)

Author: brianseeders

packages/kbn-es/src/cluster.js

@@ -275,6 +275,15 @@ exports.Cluster = class Cluster {
 
     this._log.debug('%s %s', ES_BIN, args.join(' '));
 
+    options.esEnvVars = options.esEnvVars || {};
+
+    // ES now automatically sets heap size to 50% of the machine's available memory
+    // so we need to set it to a smaller size for local dev and CI
+    // especially because we currently run many instances of ES on the same machine during CI
+    options.esEnvVars.ES_JAVA_OPTS =
+      (options.esEnvVars.ES_JAVA_OPTS ? `${options.esEnvVars.ES_JAVA_OPTS} ` : '') +
+      '-Xms1g -Xmx1g';
+
     this._process = execa(ES_BIN, args, {
       cwd: installPath,
       env: {