perf($Druid): dynamic connection pool size

BREAKING CHANGE: dynamic connection pool size, set by CPU core count

spring-cloud-starter/src/main/java/com/jmsoftware/maf/springcloudstarter/database/DataSourceConfiguration.java

@@ -29,6 +29,12 @@
 @Slf4j
 @ConditionalOnClass({MybatisPlusAutoConfiguration.class})
 public class DataSourceConfiguration {
+    @Bean
+    public DruidDataSourceCreatorPostProcessor druidDataSourceCreatorPostProcessor() {
+        log.warn("Initial bean: '{}'", DruidDataSourceCreatorPostProcessor.class.getSimpleName());
+        return new DruidDataSourceCreatorPostProcessor();
+    }
+
     /**
      * Primary data source. Had to configure DynamicRoutingDataSource as primary. Otherwise
      * MasterSlaveAutoRoutingPlugin will not be able to be injected datasource correctly.

spring-cloud-starter/src/main/java/com/jmsoftware/maf/springcloudstarter/database/DruidDataSourceCreatorPostProcessor.java

@@ -0,0 +1,34 @@
+package com.jmsoftware.maf.springcloudstarter.database;
+
+import com.baomidou.dynamic.datasource.creator.DruidDataSourceCreator;
+import lombok.extern.slf4j.Slf4j;
+import lombok.val;
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.config.BeanPostProcessor;
+import org.springframework.lang.NonNull;
+import org.springframework.lang.Nullable;
+
+/**
+ * Description: DruidDataSourceCreatorPostProcessor, change description here.
+ *
+ * @author Johnny Miller (锺俊), email: johnnysviva@outlook.com, date: 8/25/2021 11:27 AM
+ **/
+@Slf4j
+public class DruidDataSourceCreatorPostProcessor implements BeanPostProcessor {
+    @Nullable
+    @Override
+    public Object postProcessAfterInitialization(@NonNull Object bean, @NonNull String beanName) throws BeansException {
+        if (bean instanceof DruidDataSourceCreator) {
+            this.postProcessDynamicDataSourceProperties((DruidDataSourceCreator) bean);
+        }
+        return bean;
+    }
+
+    private void postProcessDynamicDataSourceProperties(DruidDataSourceCreator bean) {
+        val cpuCoreCount = Runtime.getRuntime().availableProcessors();
+        val druidConfig = bean.getGConfig();
+        log.warn("Setting Druid connection pool by current cpuCoreCount: {}", cpuCoreCount);
+        druidConfig.setInitialSize(cpuCoreCount);
+        druidConfig.setMaxActive(cpuCoreCount * 2 + 1);
+    }
+}