是分布式计算领域的旗帜性人物和开源社区领袖，同时是国际知名开源项目 Codis 作者。 Codis 是基于 Redis 的分布式集群解决方案， 为用户提供在线弹性伸缩和高性能的缓存服务，该项目 目前已广泛被各大互 联网公司（百度/小米/滴滴/猎豹 等）采用。 核心技术团队均为一线互联网公司基础架构部资深架构师，有技术改变世界的强烈抱负。 2013年以后 2008年至2013年 2008年以前 • 背景：应用最为广泛的数据库；能 业务）和华为商城（VMall）等大型项目落地 京东 全职工程师（10人团队）深度参与，将会在京 东云平台落地，替 换内部 Oracle，继阿里去IOE之后又一重大标志性事件 百度 已经开始整合 TiDB 的技术调研 滴滴、360、乐视、去哪儿 均有浓厚兴趣，后续合作正在洽谈 渠道 多个Pass服务商 主动希望为其客户提供分布式数据库解决方案（云服务） 客户 多个客户 有明确和迫切的需求痛点，主 动提供场景进行 PoC

将配置 Spring 命名空间的 xml 通过 Spring 启动，作业将自动加载。 表结构说明 事 件 追 踪 的 event_trace_rdb_url 属 性 对 应 库 自 动 创 建 JOB_EXECUTION_LOG 和 JOB_STATUS_TRACE_LOG 两张表以及若干索引。 JOB_EXECUTION_LOG 字段含义 字段名称 字段类型 是否必 填 描述 id VAR‐ failure_cause(如果作业执 行失败)。 6.1. 使用手册 49 Apache ShardingSphere ElasticJob document JOB_STATUS_TRACE_LOG 字段含义 JOB_STATUS_TRACE_LOG 记录作业状态变更痕迹表。可通过每次作业运行的 task_id 查询作业状态变化 的生命周期和运行轨迹。 6.1.4 操作 API ElasticJob 提供了 Root Config • � Job Types – � Simple – � Dataflow – � Script – � Http（3.0.0‐beta 提供） • � Event Trace – � Event Publisher – � Database Event Listener – ☐ Other Event Listener • ☐ Unified Schedule

获取执⾏ SQL 消耗的 cpu stats 信息 Trace ● Use Go trace to collect runtime information. curl http://localhost:10080/debug/pprof/trace\?seconds\=1 --output trace.out go tool trace trace.out ● In Goroutine analysis Goroutine you want to view. Trace - drawback ● Large performance impact. ● May generate a lot of trace data, and then parsing this data is also consume a lot of time. How Go trace works? Time(ms) Event 50 GoUnpark 1 goroutine 没有被 block 了 60 GoStart 1 开始运⾏ goroutine 80 GoEnd 1 结束 goroutine How Go trace works? Time(ms) Event goroutine_id description 0 GoCreate 1 创建⼀个 goroutine 10 GoStart 1 开始运⾏ goroutine

OpenTracing ○ Zipkin ○ Uber Jaeger ● OpenCensus ● OpenTracing + OpenCensus = OpenTelemetry 基本概念：Trace & Span Trace & Span 例子 Jaeger ● CNCF 毕业项目 ● 实现 OpenTracing 标准 ● UI 友好 ● 多种 Sampling 策略 ● 后端存储分离 ● instrumentedsql luna-duclos/instrumentedsql: A sql driver that will wrap any other driver and log/trace all its calls instrumentedsql 原理 在 Driver 相关的调用加 Wrapper 插入 Span 真实的数据库调用对我们来说还是 黑洞 少废话先看东西 Network Ready Goroutine Wakeup 4.368ms go tool trace go tool trace ● 优点：好用，好看（UI） ● 缺点：性能损耗太大，不能一直开着 Trace in Go runtime ● go tool trace 的原理是？ Trace 会 Go Runtime 的代码中打桩收集 CPU time，在 Goroutine 开始执行时记录

Job Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 Event Trace Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 6.2.7 Spring Namespace Focus business SDK, can work with Spring IOC • Admin Console – Job administration – Job event trace query – Registry center management 3 3 Environment Required 3.1 Java Java 8 or above required which is the value of the event tracing property event_trace_rdb_url will automati‐ cally create two tables JOB_EXECUTION_LOG and JOB_STATUS_TRACE_LOG and several indexes. 6.1. Usage 47 Apache ShardingSphere

optimizer_switch ReservedConn optimizer_trace ReservedConn optimizer_trace_features ReservedConn 23 System variable Handled optimizer_trace_limit ReservedConn optimizer_trace_max_mem_size ReservedConn transaction_isolation transaction_isolation ReservedConn tx_isolation ReservedConn optimizer_trace_offset ReservedConn parser_max_mem_size ReservedConn profiling ReservedConn profiling_history_size ReservedConn query_alloc_block_size before stopping (default 50ms) log_backtrace_at value when logging hits line file:N, emit a stack trace log_dir string If non-empty, write log files in this directory log_err_stacks boolean log stack traces

finding are available in . dbeaver.ini our article Add line in the end of . -Ddbeaver.jdbc.trace=true dbeaver.ini Restart DBeaver. Connect to your database and browse the metadata in the database queries with results. jdbc-api-trace.log Analyzing contents of you can understand what is wrong with the metadata. Attach the piece jdbc-api-trace.log of the trace file in the GitHub ticket if you DBeaver's side. WARNING: disable JDBC tracing in your regular work. Enable it only for debugging. The trace generation decreases application performance and may produce huge log files. JDBC tracing DBeaver

finding are available in . dbeaver.ini our article Add line in the end of . -Ddbeaver.jdbc.trace=true dbeaver.ini Restart DBeaver. Connect to your database and browse the metadata in the database queries with results. jdbc-api-trace.log Analyzing contents of you can understand what is wrong with the metadata. Attach the piece jdbc-api-trace.log of the trace file in the GitHub ticket if you DBeaver's side. WARNING: disable JDBC tracing in your regular work. Enable it only for debugging. The trace generation decreases application performance and may produce huge log files. JDBC tracing DBeaver

ReservedConn optimizer_switch ReservedConn optimizer_trace ReservedConn optimizer_trace_features ReservedConn optimizer_trace_limit ReservedConn optimizer_trace_max_mem_size ReservedConn transaction_isolation n ReservedConn tx_isolation ReservedConn optimizer_trace_offset ReservedConn parser_max_mem_size ReservedConn 22 System variable Handled profiling ReservedConn profiling_history_size ReservedConn q before stopping (default 50ms) log_backtrace_at value when logging hits line file:N, emit a stack trace log_dir string If non-empty, write log files in this directory log_err_stacks boolean log stack traces

Pragma ................................................................................... 80 parser_trace Pragma................................................................................ 80 recursive_triggers secure_delete Pragma ............................................................................. 80 sql_trace Pragma ..................................................................................... 81 synchronous pa�se�_t�a�e P�ag�a The parser_trace pragma controls printing the debugging state as it parses SQL commands. Following is the simple syntax: PRAGMA parser_trace = [true|false]; By default, it is