现在好多公司都在使用微服务，也有一些公司在落地DDD在业务中，那么你的服务做了监控了吗？一般除了错误日志的监控，报警发邮件、飞书消息或者短信，还有的对数据库或者服务器做了一些监控，那么你对你的服务的JVM层面做了监控吗？
如果没有做JVM的监控，那么接着看下面的内容，告诉你一个SpringBoot的微服务怎么去做JVM层面的监控？
SpringBoot应用JVM监控实践DEMO
一、 在服务中增加依赖
二、 增加Springboot Actuator 和promethus配置
增加的Springboot Actuator的配置如下所示
增加的prometheus的配置如下：
启动Springboot应用后，使用如下URL可以观察到如下响应：
请求：
代码语言：javascript复制http://ip:port/actuator/prometheus响应：
代码语言：javascript复制# HELP jvm_gc_memory_promoted_bytes_total Count of positive increases in the size of the old generation memory pool before GC to after GC
# TYPE jvm_gc_memory_promoted_bytes_total counter
jvm_gc_memory_promoted_bytes_total 3.74492E7
# HELP jvm_buffer_count_buffers An estimate of the number of buffers in the pool
# TYPE jvm_buffer_count_buffers gauge
jvm_buffer_count_buffers{id="direct",} 5.0
jvm_buffer_count_buffers{id="mapped",} 0.0
# HELP jvm_gc_live_data_size_bytes Size of old generation memory pool after a full GC
# TYPE jvm_gc_live_data_size_bytes gauge
jvm_gc_live_data_size_bytes 5.3624472E7
# HELP jvm_threads_states_threads The current number of threads having NEW state
# TYPE jvm_threads_states_threads gauge
jvm_threads_states_threads{state="runnable",} 49.0
jvm_threads_states_threads{state="blocked",} 0.0
jvm_threads_states_threads{state="waiting",} 44.0
jvm_threads_states_threads{state="timed-waiting",} 35.0
jvm_threads_states_threads{state="new",} 0.0
jvm_threads_states_threads{state="terminated",} 0.0
# HELP spring_integration_channels The number of message channels
# TYPE spring_integration_channels gauge
spring_integration_channels 2.0
# HELP jvm_memory_max_bytes The maximum amount of memory in bytes that can be used for memory management
# TYPE jvm_memory_max_bytes gauge
jvm_memory_max_bytes{area="heap",id="PS Survivor Space",} 3.145728E7
jvm_memory_max_bytes{area="heap",id="PS Old Gen",} 2.845310976E9
jvm_memory_max_bytes{area="heap",id="PS Eden Space",} 1.354235904E9
jvm_memory_max_bytes{area="nonheap",id="Metaspace",} -1.0
jvm_memory_max_bytes{area="nonheap",id="Code Cache",} 2.5165824E8
jvm_memory_max_bytes{area="nonheap",id="Compressed Class Space",} 1.073741824E9
# HELP jvm_memory_committed_bytes The amount of memory in bytes that is committed for the Java virtual machine to use
# TYPE jvm_memory_committed_bytes gauge
jvm_memory_committed_bytes{area="heap",id="PS Survivor Space",} 3.145728E7
jvm_memory_committed_bytes{area="heap",id="PS Old Gen",} 2.63192576E8
jvm_memory_committed_bytes{area="heap",id="PS Eden Space",} 3.55991552E8
jvm_memory_committed_bytes{area="nonheap",id="Metaspace",} 8.5458944E7
jvm_memory_committed_bytes{area="nonheap",id="Code Cache",} 1.769472E7
jvm_memory_committed_bytes{area="nonheap",id="Compressed Class Space",} 1.1010048E7
# HELP tomcat_sessions_active_current_sessions
# TYPE tomcat_sessions_active_current_sessions gauge
tomcat_sessions_active_current_sessions 0.0
# HELP logback_events_total Number of error level events that made it to the logs
# TYPE logback_events_total counter
logback_events_total{level="warn",} 12.0
logback_events_total{level="debug",} 0.0
logback_events_total{level="error",} 0.0
logback_events_total{level="trace",} 0.0
logback_events_total{level="info",} 56.0
# HELP tomcat_sessions_expired_sessions_total
# TYPE tomcat_sessions_expired_sessions_total counter
tomcat_sessions_expired_sessions_total 0.0
# HELP tomcat_sessions_alive_max_seconds
# TYPE tomcat_sessions_alive_max_seconds gauge
tomcat_sessions_alive_max_seconds 0.0
# HELP jvm_gc_memory_allocated_bytes_total Incremented for an increase in the size of the young generation memory pool after one GC to before the next
# TYPE jvm_gc_memory_allocated_bytes_total counter
jvm_gc_memory_allocated_bytes_total 1.447756672E9
# HELP process_start_time_seconds Start time of the process since unix epoch.
# TYPE process_start_time_seconds gauge
process_start_time_seconds 1.633764054233E9
# HELP jvm_memory_used_bytes The amount of used memory
# TYPE jvm_memory_used_bytes gauge
jvm_memory_used_bytes{area="heap",id="PS Survivor Space",} 3.143352E7
jvm_memory_used_bytes{area="heap",id="PS Old Gen",} 5.6170736E7
jvm_memory_used_bytes{area="heap",id="PS Eden Space",} 1.45013368E8
jvm_memory_used_bytes{area="nonheap",id="Metaspace",} 8.1185736E7
jvm_memory_used_bytes{area="nonheap",id="Code Cache",} 1.7651712E7
jvm_memory_used_bytes{area="nonheap",id="Compressed Class Space",} 1.0256224E7
# HELP system_cpu_count The number of processors available to the Java virtual machine
# TYPE system_cpu_count gauge
system_cpu_count 8.0
# HELP jvm_classes_loaded_classes The number of classes that are currently loaded in the Java virtual machine
# TYPE jvm_classes_loaded_classes gauge
jvm_classes_loaded_classes 15057.0
# HELP jvm_buffer_total_capacity_bytes An estimate of the total capacity of the buffers in this pool
# TYPE jvm_buffer_total_capacity_bytes gauge
jvm_buffer_total_capacity_bytes{id="direct",} 16400.0
jvm_buffer_total_capacity_bytes{id="mapped",} 0.0
# HELP spring_integration_sources The number of message sources
# TYPE spring_integration_sources gauge
spring_integration_sources 0.0
# HELP jvm_threads_daemon_threads The current number of live daemon threads
# TYPE jvm_threads_daemon_threads gauge
jvm_threads_daemon_threads 69.0
# HELP tomcat_sessions_created_sessions_total
# TYPE tomcat_sessions_created_sessions_total counter
tomcat_sessions_created_sessions_total 0.0
# HELP tomcat_sessions_rejected_sessions_total
# TYPE tomcat_sessions_rejected_sessions_total counter
tomcat_sessions_rejected_sessions_total 0.0
# HELP jvm_gc_max_data_size_bytes Max size of old generation memory pool
# TYPE jvm_gc_max_data_size_bytes gauge
jvm_gc_max_data_size_bytes 2.845310976E9
# HELP process_cpu_usage The "recent cpu usage" for the Java Virtual Machine process
# TYPE process_cpu_usage gauge
process_cpu_usage 0.12716195672342906
# HELP jvm_buffer_memory_used_bytes An estimate of the memory that the Java virtual machine is using for this buffer pool
# TYPE jvm_buffer_memory_used_bytes gauge
jvm_buffer_memory_used_bytes{id="direct",} 16402.0
jvm_buffer_memory_used_bytes{id="mapped",} 0.0
# HELP tomcat_sessions_active_max_sessions
# TYPE tomcat_sessions_active_max_sessions gauge
tomcat_sessions_active_max_sessions 0.0
# HELP jvm_threads_live_threads The current number of live threads including both daemon and non-daemon threads
# TYPE jvm_threads_live_threads gauge
jvm_threads_live_threads 128.0
# HELP jvm_threads_peak_threads The peak live thread count since the Java virtual machine started or peak was reset
# TYPE jvm_threads_peak_threads gauge
jvm_threads_peak_threads 128.0
# HELP jvm_classes_unloaded_classes_total The total number of classes unloaded since the Java virtual machine has started execution
# TYPE jvm_classes_unloaded_classes_total counter
jvm_classes_unloaded_classes_total 0.0
# HELP system_cpu_usage The "recent cpu usage" for the whole system
# TYPE system_cpu_usage gauge
system_cpu_usage 0.08727740040389209
# HELP spring_integration_handlers The number of message handlers
# TYPE spring_integration_handlers gauge
spring_integration_handlers 1.0
# HELP process_uptime_seconds The uptime of the Java virtual machine
# TYPE process_uptime_seconds gauge
process_uptime_seconds 252.707
# HELP jvm_gc_pause_seconds Time spent in GC pause
# TYPE jvm_gc_pause_seconds summary
jvm_gc_pause_seconds_count{action="end of major GC",cause="Metadata GC Threshold",} 1.0
jvm_gc_pause_seconds_sum{action="end of major GC",cause="Metadata GC Threshold",} 0.24
jvm_gc_pause_seconds_count{action="end of minor GC",cause="Metadata GC Threshold",} 1.0
jvm_gc_pause_seconds_sum{action="end of minor GC",cause="Metadata GC Threshold",} 0.02
jvm_gc_pause_seconds_count{action="end of minor GC",cause="Allocation Failure",} 3.0
jvm_gc_pause_seconds_sum{action="end of minor GC",cause="Allocation Failure",} 0.047
jvm_gc_pause_seconds_count{action="end of minor GC",cause="GCLocker Initiated GC",} 1.0
jvm_gc_pause_seconds_sum{action="end of minor GC",cause="GCLocker Initiated GC",} 0.018
# HELP jvm_gc_pause_seconds_max Time spent in GC pause
# TYPE jvm_gc_pause_seconds_max gauge
jvm_gc_pause_seconds_max{action="end of major GC",cause="Metadata GC Threshold",} 0.0
jvm_gc_pause_seconds_max{action="end of minor GC",cause="Metadata GC Threshold",} 0.0
jvm_gc_pause_seconds_max{action="end of minor GC",cause="Allocation Failure",} 0.0
jvm_gc_pause_seconds_max{action="end of minor GC",cause="GCLocker Initiated GC",} 0.0最终的效果如下图所示
三、 实践中遇到的问题
(一) 问题1
通过截图可以看到下面的问题：
如上类TextFormat中的Collector.Type.INFO中在低版本simpleclient 0.5.0中不存在导致该异常。
出现的原因：因为spring-cloud-starter-alibaba-nacos-discovery中依赖了0.5.0版本的simpleclient
解决方案：排除掉spring-cloud-starter-alibaba-nacos-discovery中的低版本simpleclient即可
