前言 不知不觉，口罩一戴就是两年。快到年底了，是时候翻开年初写的总结和计划，看看那个梦想中的自我和实现中的自我的距离了。如果看完这个距离，还是

把大象装入货柜里——Java容器内存拆解

缘起 还记得 15 年前，外企还是相当部分程序员的向往。而 2021 了，情况有了相当大的变化。开源界也有相当多的国人开源项目和文档了。所以很多新码农开始提出

小众 iSCSI 简介

CPU Benchmark The SysBench system benchmark suite has a simple CPU benchmark tool that calculates prime numbers. For example: # sysbench --num-threads=8 --test=cpu --cpu-max-prime=100000 run sysbench 0.4.12: multi-threaded system evaluation benchmark Running the test with following options: Number of threads: 8 Doing CPU performance benchmark Threads started! Done. Maximum prime number checked in CPU test: 100000 Test execution summary: total time: 30.4125s total number of events: 10000 total time taken by event execution: 243.

Jobs SIGHUP 默认动作：Terminate 可能动作：Terminate, Ignore, Function call 当检测到 hangup 时，UART 驱动会向整个 session 发送 SIGHUP 信号。 正常情况下，这会 kill 掉所有

k6 https://github.com/k6io/k6 Locust https://docs.locust.io/en/stable/what-is-locust.html gatling https://gatling.io/docs/current/http/http_request/ artillery https://artillery.io/docs/guides/overview/welcome.html wrk https://github.com/wg/wrk

内置 Classloader Class loaders load classes and resources present on their respective classpath: System or application class loaders load classes from the application classpath Extension class loaders search on the Extension classpath (JRE/lib/ext) Bootstrap class loader looks on the Bootstrap classpath (JRE/lib/rt.jar) We can customize the default class loading behavior as well. We can explicitly specify the class loader while loading a class dynamically. However, we should note that

https://github.com/open-telemetry/opentelemetry-java-instrumentation/blob/main/docs/contributing/javaagent-jar-components.md Conf Creating spans around methods with otel.instrumentation.methods.include Ref: https://github.com/open-telemetry/opentelemetry-java-instrumentation/blob/main/docs/manual-instrumentation.md Format is "java -Dotel.instrumentation.methods.include=my.package.MyClass1[method1,method2];my.package.MyClass2[method3]" Classloader [arthas@16908]$ classloader -t +-BootstrapClassLoader +-io.opentelemetry.javaagent.bootstrap.AgentClassLoader@379619aa +-sun.misc.Launcher$ExtClassLoader@41fa769c +-com.taobao.arthas.agent.ArthasClassloader@3697b340 +-sun.misc.Launcher$AppClassLoader@18b4aac2 +-java.net.URLClassLoader@71b2d611 +-java.net.URLClassLoader@69cd1085 | +-WebAppClassLoader=266661735@fe4ef67 | | +-com.mycom.sig.foundation.servicediscovery.ExtendedClassLoader@573f7aae | +-WebAppClassLoader=Server Initiated@1ccb04b3 | | +-com.mycom.sig.foundation.servicediscovery.ExtendedClassLoader@4b3b9a06 | | +-jnr.ffi.provider.jffi.AsmClassLoader@73cb9ccb | | +-jnr.ffi.provider.jffi.AsmClassLoader@7c380e94 | | +-jnr.ffi.provider.jffi.AsmClassLoader@69ec5d1f | +-WebAppClassLoader=OAuth Server@10d98940 | | +-com.mycom.ece.common.svcfinder.ExtendedClassLoader@3528968e | | +-com.mycom.sig.foundation.servicediscovery.ExtendedClassLoader@2919aff3 | | +-jnr.ffi.provider.jffi.AsmClassLoader@1b0e6bac | | +-jnr.ffi.provider.jffi.AsmClassLoader@2f12d8d1 | | +-jnr.ffi.provider.jffi.AsmClassLoader@73123f21 | +-WebAppClassLoader=1133988396@43974a2c | +-com.mycom.sig.foundation.servicediscovery.ExtendedClassLoader@39d87c5f +-java.net.URLClassLoader@1b4c457c +-java.net.URLClassLoader@3a477cf5 Affect(row-cnt:24)

Custom Resource 的入口 请求是这样分发到 api 扩展点的： 例如我们有 （Custom Resource）CR 1 2 3 4 5 6 7 8 apiVersion: cnat.programming-kubernetes.info/v1alpha1 kind: At metadata: name: example-at spec: schedule: "2019-07-03T02:00:00Z" status: phase: "pending" 相应的 CustomResourceDefinition (CRD) 会是

API 入口 Client Sets 接收变更通知和缓存（Informers and Caching） Client Sets可以 watch 变更，但一般我们用更高级的 Informers，因为它有缓存

Concept umbrella chart you can also create a chart with dependencies to other charts (a.k.a. umbrella chart) which are completely external using the requirements.yaml file. versioning Simple 1-1 versioning Chart versus application versioning 参考 https://codefresh.io/docs/docs/new-helm/helm-best-practices/

前言 最近由于工作需要，重新系统回顾 Kubernetes 的编程。发现《Programming Kubernetes》这书写得比较系统。于是边学，边记录一些重点。 Controller