apache ignite config sample https://apacheignite.readme.io/docs/memory-configuration

default-config.xml

<?xml version="1.0" encoding="UTF-8"?>

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  this work for additional information regarding copyright ownership.
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<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd">
    <!--
        Alter configuration below as needed.
    -->
    <bean id="grid.cfg" class="org.apache.ignite.configuration.IgniteConfiguration">
      <property name="dataStorageConfiguration">
        <bean class="org.apache.ignite.configuration.DataStorageConfiguration">
          <property name="defaultDataRegionConfiguration">
            <bean class="org.apache.ignite.configuration.DataRegionConfiguration">
              <property name="name" value="Default_Region"/>
              <property name="initialSize" value="#{1L * 1024 * 1024 * 1024}"/>
              <property name="maxSize" value="#{16L * 1024 * 1024 * 1024}"/>
              <property name="persistenceEnabled" value="false"/>
            </bean>
          </property>
        </bean>
      </property>
    </bean>
</beans>