Merge branch 'develop' of github.com:taosdata/TDengine into szhou/feature/support-math-functions

.drone.yml

 ---
 kind: pipeline
-name: test_amd64
-
-platform:
-  os: linux
-  arch: amd64
-
-steps:
-- name: build
-  image: gcc
-  commands:
-  - apt-get update
-  - apt-get install -y cmake build-essential 
-  - git submodule update --init --recursive
-  - mkdir debug
-  - cd debug
-  - cmake .. 
-  - make -j4 
-  trigger:
-    event:
-      - pull_request
-  when:
-    branch:
-    - develop
-    - master
-    - 2.0
----
-kind: pipeline
 name: test_arm64_bionic
 
 platform:
@@ -37,7 +10,10 @@ steps:
   image: arm64v8/ubuntu:bionic
   commands:
   - apt-get update
-  - apt-get install -y cmake build-essential
+  - apt-get install -y cmake  git build-essential wget
+  - wget https://dl.google.com/go/go1.16.9.linux-arm64.tar.gz
+  - tar -C /usr/local -xzf go1.16.9.linux-arm64.tar.gz
+  - export PATH=$PATH:/usr/local/go/bin
   - git submodule update --init --recursive
   - mkdir debug
   - cd debug
@@ -65,7 +41,10 @@ steps:
   commands:
   - echo 'debconf debconf/frontend select Noninteractive' | debconf-set-selections
   - apt-get update 
-  - apt-get install -y -qq cmake build-essential
+  - apt-get install -y -qq git cmake build-essential wget
+  - wget https://dl.google.com/go/go1.16.9.linux-arm64.tar.gz
+  - tar -C /usr/local -xzf go1.16.9.linux-arm64.tar.gz
+  - export PATH=$PATH:/usr/local/go/bin
   - git submodule update --init --recursive
   - mkdir debug
   - cd debug
@@ -91,11 +70,17 @@ steps:
 - name: build
   image: arm64v8/centos:7
   commands:
-  - yum install -y gcc gcc-c++ make cmake git
+  - yum install -y epel-release
+  - yum install -y gcc gcc-c++ make cmake3  wget git 
+  - wget https://dl.google.com/go/go1.16.9.linux-arm64.tar.gz
+  - tar -C /usr/local -xzf go1.16.9.linux-arm64.tar.gz
+  - export PATH=$PATH:/usr/local/go/bin
+  - ln -s /usr/bin/cmake3 /usr/bin/cmake
+  - go version
   - git submodule update --init --recursive
   - mkdir debug
   - cd debug
-  - cmake .. -DCPUTYPE=aarch64 > /dev/null
+  - cmake3 .. -DCPUTYPE=aarch64 > /dev/null
   - make -j4 
   trigger:
     event:
@@ -117,7 +102,7 @@ steps:
 - name: build
   image: arm64v8/centos:8
   commands:
-  - dnf install -y gcc gcc-c++ make cmake epel-release git libarchive
+  - dnf install -y gcc gcc-c++ make cmake epel-release git libarchive golang
   - git submodule update --init --recursive
   - mkdir debug
   - cd debug
@@ -144,7 +129,7 @@ steps:
   image: arm32v7/ubuntu:bionic
   commands:
   - apt-get update
-  - apt-get install -y cmake build-essential
+  - apt-get install -y cmake build-essential golang-go git
   - git submodule update --init --recursive
   - mkdir debug
   - cd debug
@@ -171,7 +156,10 @@ steps:
   image: ubuntu:trusty
   commands:
   - apt-get update
-  - apt-get install -y gcc cmake3 build-essential git binutils-2.26
+  - apt-get install -y gcc cmake3 build-essential git binutils-2.26 wget 
+  - wget https://dl.google.com/go/go1.16.9.linux-amd64.tar.gz
+  - tar -C /usr/local -xzf go1.16.9.linux-amd64.tar.gz
+  - export PATH=$PATH:/usr/local/go/bin
   - git submodule update --init --recursive
   - mkdir debug
   - cd debug
@@ -198,7 +186,10 @@ steps:
   image: ubuntu:xenial
   commands:
   - apt-get update
-  - apt-get install -y gcc cmake build-essential
+  - apt-get install -y gcc cmake build-essential  git wget
+  - wget https://dl.google.com/go/go1.16.9.linux-amd64.tar.gz
+  - tar -C /usr/local -xzf go1.16.9.linux-amd64.tar.gz
+  - export PATH=$PATH:/usr/local/go/bin
   - git submodule update --init --recursive
   - mkdir debug
   - cd debug
@@ -224,7 +215,10 @@ steps:
   image: ubuntu:bionic
   commands:
   - apt-get update
-  - apt-get install -y gcc cmake build-essential
+  - apt-get install -y gcc cmake build-essential  git wget
+  - wget https://dl.google.com/go/go1.16.9.linux-amd64.tar.gz
+  - tar -C /usr/local -xzf go1.16.9.linux-amd64.tar.gz
+  - export PATH=$PATH:/usr/local/go/bin
   - git submodule update --init --recursive
   - mkdir debug
   - cd debug
@@ -249,11 +243,16 @@ steps:
 - name: build
   image: ansible/centos7-ansible
   commands:
-  - yum install -y gcc gcc-c++ make cmake
+  - yum install -y epel-release
+  - yum install -y gcc gcc-c++ make cmake3  wget git 
+  - wget https://dl.google.com/go/go1.16.9.linux-amd64.tar.gz
+  - tar -C /usr/local -xzf go1.16.9.linux-amd64.tar.gz
+  - export PATH=$PATH:/usr/local/go/bin
+  - ln -s /usr/bin/cmake3 /usr/bin/cmake
   - git submodule update --init --recursive
   - mkdir debug
   - cd debug
-  - cmake .. 
+  - cmake3 .. 
   - make -j4 
   trigger:
     event:

CMakeLists.txt

@@ -10,9 +10,9 @@ ELSE ()
 ENDIF ()
 
 IF (${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
-  CMAKE_MINIMUM_REQUIRED(VERSION 2.8...3.20)
+  CMAKE_MINIMUM_REQUIRED(VERSION 3.0...3.20)
 ELSE ()
-  CMAKE_MINIMUM_REQUIRED(VERSION 2.8)
+  CMAKE_MINIMUM_REQUIRED(VERSION 3.0)
 ENDIF ()
 
 SET(TD_ACCOUNT FALSE)
@@ -38,7 +38,7 @@ MESSAGE(STATUS "Community directory: " ${TD_COMMUNITY_DIR})
 INCLUDE(cmake/input.inc)
 INCLUDE(cmake/platform.inc)
 
-IF (TD_WINDOWS OR TD_DARWIN) 
+IF (TD_WINDOWS OR TD_DARWIN)
   SET(TD_SOMODE_STATIC TRUE)
 ENDIF ()
 

Jenkinsfile

 import hudson.model.Result
 import hudson.model.*;
 import jenkins.model.CauseOfInterruption
-properties([pipelineTriggers([githubPush()])])
 node {
-    git url: 'https://github.com/taosdata/TDengine.git'
 }
 
 def skipbuild=0
@@ -99,7 +97,7 @@ def pre_test(){
     sh '''
     cd ${WK}
     git pull >/dev/null 
-    git submodule update --init --recursive
+    
     export TZ=Asia/Harbin
     date
     git clean -dfx
@@ -149,6 +147,7 @@ def pre_test_win(){
     git fetch origin +refs/pull/%CHANGE_ID%/merge
     git checkout -qf FETCH_HEAD
     git clean -dfx
+    git submodule update --init --recursive
     cd C:\\workspace\\TDinternal
     git reset --hard HEAD~10
     '''
@@ -193,6 +192,7 @@ def pre_test_win(){
 }
 pipeline {
   agent none
+  options { skipDefaultCheckout() } 
   environment{
       WK = '/var/lib/jenkins/workspace/TDinternal'
       WKC= '/var/lib/jenkins/workspace/TDinternal/community'
@@ -200,67 +200,67 @@ pipeline {
   stages {
       stage('pre_build'){
           agent{label 'master'}
-          when {
-              changeRequest()
+          options { skipDefaultCheckout() } 
+          when{
+                changeRequest()
           }
           steps {
             script{
               abort_previous()
               abortPreviousBuilds()
             }
-          sh'''
-          rm -rf ${WORKSPACE}.tes
-          cp -r ${WORKSPACE} ${WORKSPACE}.tes
-          cd ${WORKSPACE}.tes
-          git fetch
-          '''
-          script {
-            if (env.CHANGE_TARGET == 'master') {
-              sh '''
-              git checkout master
-              '''
-              }
-            else if(env.CHANGE_TARGET == '2.0'){
-              sh '''
-              git checkout 2.0
-              '''
-            } 
-            else{
-              sh '''
-              git checkout develop
-              '''
-            } 
-          }
-          sh'''
-          git fetch origin +refs/pull/${CHANGE_ID}/merge
-          git checkout -qf FETCH_HEAD
-          '''     
+          //   sh'''
+          // rm -rf ${WORKSPACE}.tes
+          // cp -r ${WORKSPACE} ${WORKSPACE}.tes
+          // cd ${WORKSPACE}.tes
+          // git fetch
+          // '''
+          // script {
+          //   if (env.CHANGE_TARGET == 'master') {
+          //     sh '''
+          //     git checkout master
+          //     '''
+          //     }
+          //   else if(env.CHANGE_TARGET == '2.0'){
+          //     sh '''
+          //     git checkout 2.0
+          //     '''
+          //   } 
+          //   else{
+          //     sh '''
+          //     git checkout develop
+          //     '''
+          //   } 
+          // }
+          // sh'''
+          // git fetch origin +refs/pull/${CHANGE_ID}/merge
+          // git checkout -qf FETCH_HEAD
+          // '''     
 
-          script{  
-            skipbuild='2'     
-            skipbuild=sh(script: "git log -2 --pretty=%B | fgrep -ie '[skip ci]' -e '[ci skip]' && echo 1 || echo 2", returnStdout:true)
-            println skipbuild
-          }
-          sh'''
-          rm -rf ${WORKSPACE}.tes
-          '''
+          // script{  
+          //   skipbuild='2'     
+          //   skipbuild=sh(script: "git log -2 --pretty=%B | fgrep -ie '[skip ci]' -e '[ci skip]' && echo 1 || echo 2", returnStdout:true)
+          //   println skipbuild
+          // }
+          // sh'''
+          // rm -rf ${WORKSPACE}.tes
+          // '''
+          // }       
           }
       }
       stage('Parallel test stage') {
         //only build pr
+        options { skipDefaultCheckout() } 
         when {
           allOf{
               changeRequest()
-               expression{
-                return skipbuild.trim() == '2'
-              }
+              not{ expression { env.CHANGE_BRANCH =~ /docs\// }}
             }
           }
       parallel {
         stage('python_1_s1') {
           agent{label " slave1 || slave11 "}
           steps {
-            
             pre_test()
             timeout(time: 55, unit: 'MINUTES'){
               sh '''
@@ -421,11 +421,12 @@ pipeline {
               ./test-all.sh b4fq
               cd ${WKC}/tests
               ./test-all.sh p4
-              cd ${WKC}/tests
-              ./test-all.sh full jdbc
-              cd ${WKC}/tests
-              ./test-all.sh full unit
-              date'''
+              '''
+              // cd ${WKC}/tests
+              // ./test-all.sh full jdbc
+              // cd ${WKC}/tests
+              // ./test-all.sh full unit
+              
             }
           }
         }
@@ -469,35 +470,35 @@ pipeline {
           }
         } 
         
-        stage('build'){
-          agent{label " wintest "}
-          steps {
-            pre_test()
-            script{             
-                while(win_stop == 0){
-                  sleep(1)
-                  }
-              }
-            }
-        }
-        stage('test'){
-          agent{label "win"}
-          steps{
+        // stage('build'){
+        //   agent{label " wintest "}
+        //   steps {
+        //     pre_test()
+        //     script{             
+        //         while(win_stop == 0){
+        //           sleep(1)
+        //           }
+        //       }
+        //     }
+        // }
+        // stage('test'){
+        //   agent{label "win"}
+        //   steps{
             
-            catchError(buildResult: 'FAILURE', stageResult: 'FAILURE') {
-                pre_test_win()
-                timeout(time: 20, unit: 'MINUTES'){
-                bat'''
-                cd C:\\workspace\\TDinternal\\community\\tests\\pytest
-                .\\test-all.bat Wintest
-                '''
-                }
-            }     
-            script{
-              win_stop=1
-            }
-          }
-        }
+        //     catchError(buildResult: 'FAILURE', stageResult: 'FAILURE') {
+        //         pre_test_win()
+        //         timeout(time: 20, unit: 'MINUTES'){
+        //         bat'''
+        //         cd C:\\workspace\\TDinternal\\community\\tests\\pytest
+        //         .\\test-all.bat Wintest
+        //         '''
+        //         }
+        //     }     
+        //     script{
+        //       win_stop=1
+        //     }
+        //   }
+        // }
           
                
     }

README.md

@@ -6,7 +6,7 @@
 
 [![TDengine](TDenginelogo.png)](https://www.taosdata.com)
 
-English | [简体中文](./README-CN.md) 
+English | [简体中文](./README-CN.md)
 We are hiring, check [here](https://www.taosdata.com/en/careers/)
 
 # What is TDengine？
@@ -32,7 +32,7 @@ For user manual, system design and architecture, engineering blogs, refer to [TD
 # Building
 At the moment, TDengine only supports building and running on Linux systems. You can choose to [install from packages](https://www.taosdata.com/en/getting-started/#Install-from-Package) or from the source code. This quick guide is for installation from the source only.
 
-To build TDengine, use [CMake](https://cmake.org/) 2.8.12.x or higher versions in the project directory. 
+To build TDengine, use [CMake](https://cmake.org/) 3.0.2 or higher versions in the project directory.
 
 ## Install tools
 
@@ -47,7 +47,7 @@ sudo apt-get install -y gcc cmake3 build-essential git binutils-2.26
 export PATH=/usr/lib/binutils-2.26/bin:$PATH
 ```
 
-To compile and package the JDBC driver source code, you should have a Java jdk-8 or higher and Apache Maven 2.7 or higher installed. 
+To compile and package the JDBC driver source code, you should have a Java jdk-8 or higher and Apache Maven 2.7 or higher installed.
 To install openjdk-8:
 ```bash
 sudo apt-get install -y openjdk-8-jdk
@@ -60,7 +60,10 @@ sudo apt-get install -y  maven
 
 ### Centos 7:
 ```bash
-sudo yum install -y gcc gcc-c++ make cmake git
+sudo yum install epel-release
+sudo yum update
+sudo yum install -y gcc gcc-c++ make cmake3 git
+sudo ln -sf /usr/bin/cmake3 /usr/bin/cmake
 ```
 
 To install openjdk-8:
@@ -126,6 +129,17 @@ mkdir debug && cd debug
 cmake .. && cmake --build .
 ```
 
+Note TDengine 2.3.0.0 and later use a component named 'blm3' to play http daemon role by default instead of the http daemon embedded in the early version of TDengine. The blm3 is programmed by go language. If you pull TDengine source code to the latest from an existing codebase, please execute 'git submodule update --init --recursive' to pull blm3 source code. Please install go language 1.14 or above for compiling blm3. If you meet difficulties regarding 'go mod', especially you are from China, you can use a proxy to solve the problem.
+```
+go env -w GO111MODULE=on
+go env -w GOPROXY=https://goproxy.cn,direct
+```
+
+Or you can use the following command to choose to embed old httpd too.
+```
+cmake .. -DBUILD_HTTP=true
+```
+
 You can use Jemalloc as memory allocator instead of glibc:
 ```
 apt install autoconf
@@ -236,7 +250,7 @@ In another terminal, use the TDengine shell to connect the server:
 ./build/bin/taos -c test/cfg
 ```
 
-option "-c test/cfg" specifies the system configuration file directory. 
+option "-c test/cfg" specifies the system configuration file directory.
 
 # Try TDengine
 It is easy to run SQL commands from TDengine shell which is the same as other SQL databases.

cmake/define.inc

@@ -124,17 +124,25 @@ IF (TD_APLHINE)
   MESSAGE(STATUS "aplhine is defined")
 ENDIF ()
 
-IF (TD_LINUX)
-  IF (TD_ARM_32)
-    SET(TD_BUILD_HTTP TRUE)
-    ADD_DEFINITIONS(-DHTTP_EMBEDDED)
-  ELSE ()
-    IF (TD_BUILD_HTTP)
-      ADD_DEFINITIONS(-DHTTP_EMBEDDED)
+MESSAGE("before BUILD_HTTP: " ${BUILD_HTTP})
+IF ("${BUILD_HTTP}" STREQUAL "")
+  IF (TD_LINUX)
+    IF (TD_ARM_32)
+      SET(BUILD_HTTP "true")
+    ELSE ()
+      SET(BUILD_HTTP "false")
     ENDIF ()
+  ELSE ()
+    SET(BUILD_HTTP "true")
   ENDIF ()
-ELSE ()
+ENDIF ()
+MESSAGE("after BUILD_HTTP: " ${BUILD_HTTP})
+
+IF (${BUILD_HTTP} MATCHES "true")
   SET(TD_BUILD_HTTP TRUE)
+ENDIF ()
+
+IF (TD_BUILD_HTTP)
   ADD_DEFINITIONS(-DHTTP_EMBEDDED)
 ENDIF ()
 

cmake/input.inc

@@ -92,10 +92,6 @@ ENDIF ()
 
 SET(TD_BUILD_HTTP FALSE)
 
-IF (${BUILD_HTTP} MATCHES "true")
-  SET(TD_BUILD_HTTP TRUE)
-ENDIF ()
-
 SET(TD_MEMORY_SANITIZER FALSE)
 IF (${MEMORY_SANITIZER} MATCHES "true")
   SET(TD_MEMORY_SANITIZER TRUE)

cmake/version.inc

@@ -4,7 +4,7 @@ PROJECT(TDengine)
 IF (DEFINED VERNUMBER)
   SET(TD_VER_NUMBER ${VERNUMBER})
 ELSE ()
-  SET(TD_VER_NUMBER "2.2.0.5")
+  SET(TD_VER_NUMBER "2.3.0.0")
 ENDIF ()
 
 IF (DEFINED VERCOMPATIBLE)

deps/CMakeLists.txt

 PROJECT(TDengine)
 
 IF (${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
-  CMAKE_MINIMUM_REQUIRED(VERSION 2.8...3.20)
+  CMAKE_MINIMUM_REQUIRED(VERSION 3.0...3.20)
 ELSE ()
-  CMAKE_MINIMUM_REQUIRED(VERSION 2.8)
+  CMAKE_MINIMUM_REQUIRED(VERSION 3.0)
 ENDIF ()
 
 ADD_SUBDIRECTORY(zlib-1.2.11)

deps/MQTT-C/CMakeLists.txt

-CMAKE_MINIMUM_REQUIRED(VERSION 2.8...3.20)
+CMAKE_MINIMUM_REQUIRED(VERSION 3.0...3.20)
 
 # MQTT-C build options
 option(MQTT_C_OpenSSL_SUPPORT "Build MQTT-C with OpenSSL support?" OFF)

deps/MsvcLibX/CMakeLists.txt

 PROJECT(TDengine)
 
 IF (${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
-  CMAKE_MINIMUM_REQUIRED(VERSION 2.8...3.20)
+  CMAKE_MINIMUM_REQUIRED(VERSION 3.0...3.20)
 ELSE ()
-  CMAKE_MINIMUM_REQUIRED(VERSION 2.8)
+  CMAKE_MINIMUM_REQUIRED(VERSION 3.0)
 ENDIF ()
 
 IF (TD_WINDOWS)

deps/iconv/CMakeLists.txt

-CMAKE_MINIMUM_REQUIRED(VERSION 2.8...3.20)
+CMAKE_MINIMUM_REQUIRED(VERSION 3.0...3.20)
 PROJECT(TDengine)
 
 IF (TD_WINDOWS)

deps/pthread/CMakeLists.txt

-CMAKE_MINIMUM_REQUIRED(VERSION 2.8...3.20)
+CMAKE_MINIMUM_REQUIRED(VERSION 3.0...3.20)
 PROJECT(TDengine)
 
 IF (TD_WINDOWS)

deps/regex/CMakeLists.txt

-CMAKE_MINIMUM_REQUIRED(VERSION 2.8...3.20)
+CMAKE_MINIMUM_REQUIRED(VERSION 3.0...3.20)
 PROJECT(TDengine)
 
 IF (TD_WINDOWS)

deps/wepoll/CMakeLists.txt

-CMAKE_MINIMUM_REQUIRED(VERSION 2.8...3.20)
+CMAKE_MINIMUM_REQUIRED(VERSION 3.0...3.20)
 PROJECT(TDengine)
 
 IF (TD_WINDOWS)

deps/zlib-1.2.11/CMakeLists.txt

-CMAKE_MINIMUM_REQUIRED(VERSION 2.8...3.20)
+CMAKE_MINIMUM_REQUIRED(VERSION 3.0...3.20)
 PROJECT(TDengine)
 
 IF (TD_WINDOWS)

documentation20/cn/00.index/docs.md

@@ -53,6 +53,8 @@ TDengine是一个高效的存储、查询、分析时序大数据的平台，专
 * [Schemaless 写入](/insert#schemaless)：免于预先建表，将数据直接写入时自动维护元数据结构
 * [Prometheus 写入](/insert#prometheus)：配置Prometheus, 不用任何代码，将数据直接写入
 * [Telegraf 写入](/insert#telegraf)：配置Telegraf, 不用任何代码，将采集数据直接写入
+* [collectd 直接写入](/insert#collectd)：配置 collectd，不用任何代码，将采集数据直接写入
+* [StatsD 直接写入](/insert#statsd)：配置 StatsD，不用任何代码，将采集数据直接写入
 * [EMQ X Broker](/insert#emq)：配置EMQ X，不用任何代码，就可将MQTT数据直接写入
 * [HiveMQ Broker](/insert#hivemq)：配置HiveMQ，不用任何代码，就可将MQTT数据直接写入
 
@@ -129,7 +131,7 @@ TDengine是一个高效的存储、查询、分析时序大数据的平台，专
 * [TDengine写入性能测试工具](https://www.taosdata.com/blog/2020/01/18/1166.html)
 * [IDEA数据库管理工具可视化使用TDengine](https://www.taosdata.com/blog/2020/08/27/1767.html)
 * [基于Electron开发的跨平台TDengine图形化管理工具](https://github.com/skye0207/TDengineGUI)
-* [DataX，支持TDengine的离线数据采集/同步工具](https://github.com/wgzhao/DataX)（文档：[读取插件](https://github.com/wgzhao/DataX/blob/master/docs/src/main/sphinx/reader/tdenginereader.md)、[写入插件](https://github.com/wgzhao/DataX/blob/master/docs/src/main/sphinx/writer/tdenginewriter.md)）
+* [基于DataX的TDeninge数据迁移工具](https://www.taosdata.com/blog/2021/10/26/3156.html)
 
 ## TDengine与其他数据库的对比测试
 

documentation20/cn/13.faq/docs.md

@@ -183,7 +183,25 @@ TDengine 中时间戳的时区总是由客户端进行处理，而与服务端
 | TCP | 6035      | 多节点集群的节点间通讯。            | 随 serverPort 端口变化。        |
 | TCP | 6040      | 多节点集群的节点间数据同步。        | 随 serverPort 端口变化。         |
 | TCP | 6041      | 客户端与服务端之间的 RESTful 通讯。 | 随 serverPort 端口变化。        |
-| TCP | 6042      | Arbitrator 的服务端口。           | 因 Arbitrator 启动参数设置变化。 |
+| TCP | 6042      | Arbitrator 的服务端口。           | 随 Arbitrator 启动参数设置变化。 |
+| TCP | 6043      | TaosKeeper 监控服务端口。         | 随 TaosKeeper 启动参数设置变化。 |
+| TCP | 6044      | 支持 StatsD 的数据接入端口。       | 随 BLM3 启动参数设置变化（2.3.0.1+以上版本）。 |
+| TCP | 6045      | 支持 collectd 数据接入端口。       | 随 BLM3 启动参数设置变化（2.3.0.1+以上版本）。 |
 | TCP | 6060      | 企业版内 Monitor 服务的网络端口。   |                               |
 | UDP | 6030-6034 | 客户端与服务端之间通讯。            | 随 serverPort 端口变化。        |
 | UDP | 6035-6039 | 多节点集群的节点间通讯。            | 随 serverPort 端口变化。        |
+
+## 20. go 语言编写组件编译失败怎样解决？
+
+新版本 TDengine 2.3.0.0 包含一个使用 go 语言开发的 BLM3 组件，取代之前内置的 httpd ，提供包含原  httpd 功能以及支持多种其他软件（Prometheus、Telegraf、collectd、StatsD等）的数据接入功能。
+使用最新 develop 分支代码编译需要先 `git submodule update --init --recursive` 下载 blm3 仓库代码后再编译。
+
+目前编译方式默认自动编译 blm3。go 语言版本要求 1.14 以上，如果发生 go 编译错误，往往是国内访问 go mod 问题，可以通过设置 go 环境变量来解决：
+
+```sh
+go env -w GO111MODULE=on
+go env -w GOPROXY=https://goproxy.cn,direct
+```
+
+如果希望继续使用之前的内置 httpd，可以关闭 blm3 编译，使用 
+`cmake .. -DBUILD_HTTP=true` 使用原来内置的 httpd。

documentation20/cn/14.devops/01.telegraf/docs.md

@@ -39,17 +39,18 @@ IT 运维监测数据通常都是对时间特性比较敏感的数据，例如
 ```
 
 ### 修改 /etc/telegraf/telegraf.conf 
-假设 TDengine 使用默认用户名 root 和密码 taosdata。增加如下文字：
+配置方法，在 /etc/telegraf/telegraf.conf 增加如下文字，其中 database name 请填写希望在 TDengine 保存 Telegraf 数据的数据库名，TDengine server/cluster host、username和 password 填写 TDengine 实际值：
 ```
 [[outputs.http]]
-  url = "http://<TDengine server/cluster host>:6041/influxdb/v1/write?db=metrics"
+  url = "http://<TDengine server/cluster host>:6041/influxdb/v1/write?db=<database name>"
   method = "POST"
   timeout = "5s"
-  username = "root"
-  password = "taosdata"
+  username = "<TDengine's username>"
+  password = "<TDengine's password>"
   data_format = "influx"
   influx_max_line_bytes = 250
 ```
+
 然后重启 telegraf：
 ```
 sudo systemctl start telegraf

packaging/cfg/taos.cfg

@@ -301,3 +301,6 @@ keepColumnName            1
 
 # force TCP transmission 
 # rpcForceTcp        0
+
+# unit MB. Flush vnode wal file if walSize > walFlushSize and walSize > cache*0.5*blocks
+# walFlushSize         1024