怎么在rviz看SLAM栅栏地图栅栏格的大小,及测量两点的距离。。。。

怎么在rviz看SLAM栅栏地图栅栏格的大小,及测量两点的距离。。。。

在ros上实时运行视觉slam，保存地图问题

环境：ubuntu16.04, ros kinetic, kinect v1 问题描述： 使用Kinect v1相机实时的运行由orb_slam2系统修改之后的视觉slam系统，现在无法保存运行之和的地图。有大神能帮助解决吗？最好给出具体代码 代码： ``` ```int main(int argc, char **argv) { ros::init(argc, argv, "RGBD"); ros::start(); if(argc != 3) { cerr << endl << "Usage: 1111" << endl; ros::shutdown(); return 1; } // 创建SLAM系统，并初始化所有的线程 ``` ``` orb_slam::System SLAM(argv[1],argv[2],orb_slam::System::RGBD,true); ImageGrabber igb(&SLAM); ros::NodeHandle nh; message_filters::Subscriber<sensor_msgs::Image> rgb_sub(nh, "/camera/rgb/image_color", 1); message_filters::Subscriber<sensor_msgs::Image> depth_sub(nh, "/camera/depth_registered/hw_registered/image_rect_raw", 1); typedef message_filters::sync_policies::ApproximateTime<sensor_msgs::Image, sensor_msgs::Image> sync_pol; message_filters::Synchronizer<sync_pol> sync(sync_pol(10), rgb_sub,depth_sub); sync.registerCallback(boost::bind(&ImageGrabber::GrabRGBD,&igb,_1,_2)); pcl::PointCloud<pcl::PointXYZRGBA>::Ptr global_map(new pcl::PointCloud<pcl::PointXYZRGBA>); global_map = SLAM.mpPointCloudMapping->GetGlobalMap(); pcl::PointCloud<pcl::PointXYZRGB>::Ptr global_map_copy(new pcl::PointCloud<pcl::PointXYZRGB>); // signal(SIGINT, MySigintHandler); while(ros::ok())//使用ros::ok()与ros::spinOnce()搭配实现回调 { pcl::copyPointCloud(*global_map, *global_map_copy); //向topic ： /orb_slam_with_kinect1/output 发送信息，发送频率为loop_rate(10),即10hz，消息池最大容量为10. ros::Publisher pcl_pub = nh.advertise<sensor_msgs::PointCloud2> ("/orb_slam_with_kinect1/output", 10); sensor_msgs::PointCloud2 output; // 转换成ROS下的数据类型 最终通过topic发布 pcl::toROSMsg(*global_map_copy,output); output.header.stamp=ros::Time::now(); output.header.frame_id ="camera_rgb_frame"; ros::Rate loop_rate(10); pcl_pub.publish(output); ros::spinOnce(); loop_rate.sleep(); } // 保存轨迹与地图 SLAM.save(); SLAM.Shutdown(); SLAM.SaveTrajectoryTUM("CameraTrajectory.txt"); ros::shutdown(); return 0; } ``` ```

如何在Windows下实现lsd slam的点云显示

在完成了Windows下运行lsd slam后，发现没有点云显示的功能，本人看了ros下的源码，但是还是不懂怎么在Windows下实现这个功能，希望大佬能教我一下怎么实现

DSO SLAM的安装编译问题

入手了一块INDEMIND的双目摄像头打算看看V-SLAM，但在网上按照教程编译DSO到最后一步的时候遇到这这个问题。依赖库除了Pangolin暂时没装其它的应该都装全了，我看错误信息里有BOOTS，是还需要安装BOOTS库吗？但官方安装说明里也没说需要安装BOOTS呀。 百度搜索无果，特来请教各位前辈。  ! 

高翔视觉SLAM十四讲octomap安装错误

1.题主环境如下 ubuntu16.04 ros kinetic anaconda3->python3.7.3（.bashrc已注释） 按照高博书上所示，安装了doxygen，octomap编译成功... 但是octovis打不开，报错如下图片所示： 我怀疑是anaconda3的环境引起的，octovis的QT识别成了anaconda的qt，但是我把anaconda3删了还是不行。。 求大神指点！   

关于视觉SLAM第五讲jointMap的问题

 视觉SLAM14讲 joinMap程序开始部分运用了范围for， 这里fin应该是5*7的大小 为什么fin在每次循环中可以依次输出第一行，第二行，。。。第五行的7个数？而不是一直输出第一行的7个数。并没有像fin[i]这样的声明

高翔视觉SLAM十四讲第三方库安装错误问题

# 错误图片如下： ## g2o错误：  ## octomap错误  # 如题和图所示，题主在安装octomap和g2o库是遇到uuid的错误，用的Ubuntu16.04，同时装了一下anaconda3...搜遍全网都没找到solution，求大神解答呀！

ubuntu系统下ROS智能小车建出来的地图可以保存吗？

ubuntu系统下ROS智能小车在rviz上建出来的地图可以保存吗？保存下来的下一次还可以继续用吗？小车可以在这个已知的地图上知道自己的位置吗？ 我想知道的是，如果这些都可以，那么我该怎么做呢？

CartoGrapher怎么使用

刚刚接触SLAM，老师就要求用google的CartoGrapher实现一下其对室外视频的一个地图重建。 可是完全不懂，用什么IDE，在windows可以吗，看到Ubuntu+ROS indigo+rplidar，可是这是 激光SLAM，这里的输入是视频，所以应该是视觉SLAM，这样理解对吗。求解答

二维地图加入拓扑节点

基于ROS的机器人SLAM建图，如何在机器人走过的轨迹图中加入拓扑节点？？？

ORB_SLAM2编译错误,段错误,核心已转储

在做ORB_SLAM2的时候，编译已通过，运行时出错：段错误 (核心已转储)，请问怎么解决？ caomi@caomi-ubuntu:~/catkin_ws/src/ORB_SLAM2_modified$ rosrun ORB_SLAM2 RGBD Vocabulary/ORBvoc.txt Examples/RGB-D/TUM1.yaml ORB-SLAM2 Copyright (C) 2014-2016 Raul Mur-Artal, University of Zaragoza. This program comes with ABSOLUTELY NO WARRANTY; This is free software, and you are welcome to redistribute it under certain conditions. See LICENSE.txt. Input sensor was set to: RGB-D Loading ORB Vocabulary. This could take a while... Vocabulary loaded in 16.40s 段错误 (核心已转储)

Crazy Basketball Fan 问题

Problem Description Alex is a big fan of basketball and he enjoys watching NBA matches. But as he always has classes in the morning when the game is on, he has to read literal living broadcast with his cellphone instead of TV live. The living broadcast gives messages about who scores or who gets the rebound, etc. After watching a few games with his cellphone, Alex finds a problem. After each game, he wants to know the status of the players (score, rebound…) but the system always fails to give. So Alex decides to calculate himself. Can you help him? If one of your teammates is a crazy basketball fan, you should make him solve this problem because he will find it interesting while working on this problem. Input The first line of input contains an integer t (t<=10) indicate the number of cases. In each case, the first line contains the names of the two teams in the form of "A vs B", where A stands for the name of home team and B stands for the name of away team. The following 12 lines contain the name of the players play for the home team and another 12 lines contain the name of the players play for the away team. The first five players of each team will be the starters meaning they are on court when the game starts. All the names only contain letters from 'a' to 'z' and 'A' to 'Z' and ''' without space and the length of each name is no more than 20. All the players' names in one case will be different. Then a line contains an integer n (2<=n<=500) indicates the number of the messages given by the broadcast. The next n lines contain the messages, one message per line. The first line will always contain "Begin" and the last line will always contain "End". The game won't end during a shot or free throw, but may end at any other time. A message in other lines may be one of the following (x, x1 and x2 stand for players from the teams, m and M stand for numbers): Jump Ball x1 vs x2: this message will only be given on the second line right after "Begin". This means two players from different teams are jumping for the ball. This message will always be followed by "x Hold Ball" and x could be anyone. x Hold Ball: this message will be given if the ball is currently in no one's hand, which means: after jump ball or after a shot was made (including the last free throw) or after a shot was blocked or after timeout. x1 Pass to x2: this means the ball is passed from x1 to x2. x1 is deferent from x2 and they are from the same team. Layup/Slam Dunk/Hook Shot/Jump Shot/3pt Shot: the first four messages stand for an attempt for 2-point shot while the last message stand for an attempt for 3-point shot. These messages will only be given when someone is currently holding the ball. These messages may be followed by "Made"/"Missed"/"Blocked by x"/"x Foul". Made/Missed: If a shot was made and scored, "Made" will be given, otherwise "Missed". These two messages will be given right after a shot was attempted if the shot was not fouled or blocked. If the shot was fouled, these two messages will still be given right after "x Foul" to indicate whether the shot was made even with the foul. But if a shot was blocked, these messages will not be given since the shot is definitely missed. x Rebound: If a shot was missed, this message will be given to indicate who get the rebound (could be anyone from both teams). If someone gets the rebound, he holds the ball. Blocked by x: If a shot is blocked, this message will be given right after the message which indicates the shot. This message will always be followed by "x Hold Ball" and x could be anyone. A shot will only be blocked by a player from the opposite team with the shooter. x Foul: this message will be given when a player commit a foul to another player from the opposite team. There are two kind of foul. If this message is given right after the shot attempt, then this foul will lead to free throws. Otherwise this message will be followed by "x Hold Ball". Free Throw m of M: If a shot is fouled, the shooter will make free throws. If the fouled shot is made, then the shooter will only make one free throw. If it's missed and it's a 2-point shot, the shooter will make two free throws. If it's missed and it's a 3-point shot, the shooter will make three free throws. Each made free throw earns one point. In this message, m indicates the number of this free throw (start from 1) and M indicates the number of total free throws this player is going to attempt. Both m and M will be no bigger than 3 and m is no bigger than M. After each free throw there will be a message says "Made" or "Missed" to indicate whether the free throw is made or missed. If the last free throw is missed, just like normal shot, someone will get the rebound and if it's made, a player from the opposite team will hold the ball. No block could be made during the free throws. x Steal: If a player is now holding the ball, a player from the opposite team could steal the ball away. If someone steals the ball, he will hold it. x1 Substitution replaced by x2: this message means x1 is off court and replaced by x2. x1 and x2 are from the same team. This could only happen during timeout or before free throw or after a foul which doesn't lead to free throw. The player who is going to make a free throw won't be replaced. Before free throw means before any "Free Throw m of M" despite of m and M. Timeout: timeout could be called when someone is holding the ball. During timeout, substitution could be made. Timeout is ended with the message "x Hold Ball". It is guaranteed that all the messages are valid and follow the rules. The names of the players will not be the same with words like "rebound" and "block", etc. Actually all the names will be familiar to you if you watch NBA a lot. Output The first output line for each case will be "x1 n1-n2 x2", where x1 and x2 stand for the name of home team and away team and n1 and n2 stand for their total points. Then for each player from each team, calculate the number of his points, rebounds (including offensive and defensive), assists, steals, blocks and fouls. An assist is made when player x1 passes to player x2 and x2 makes a shot (2-pt or 3-pt) and then x1 gets the assist. A rebound is an offensive rebound when the shoot and the player who gets the rebound are from the same team (even the same player); otherwise it's a defensive rebound. Also you have to calculate the number of a player's made field goals (including 2-pt and 3-pt), attempted field goals (including 2-pt and 3-pt), made 3-pt shots, attempted 3-pt shots, made free throws and attempted free throws. Notice: if a shot is fouled and it's missed, it won't be counted as an attempt, but if it's fouled and made, it will be counted as an attempt and a made. The output form is shown in the sample output (PTS - points, OFF - offensive rebound, DEF - defensive rebound, REB - total rebound, AST - assist, STL - steal, BLK - block, PF - personal foul, FGM-A - field goal made and attempted, 3PM-A - 3-pt made and attempted, FTM-A - free throw made and attempted). There are 14 spaces before the word "PLAYER" and exact one space between each column. All the names and numbers are under their column and right alignment. The order of the players is the same with input. Home team first, then comes the away team. If a player didn't play at all (never on court), then you should print "DNP - Coach's Decision" 10 spaces after their names. Print a single line after each case. Sample Input 1 Lakers vs Celtics DerekFisher KobeBryant RonArtest PauGasol AndrewBynum LamarOdom MattBarnes SteveBlake ShannonBrown LukeWalton DerrickCaracter DevinEbanks RajonRondo RayAllen PaulPierce KevinGarnett ShaquilleO'Neal JeffGreen VonWafer GlenDavis JermaineO'Neal TroyMurphy NenadKrstic CarlosArroyo 17 Begin Jump Ball KevinGarnett vs PauGasol KobeBryant Hold Ball KobeBryant Pass to PauGasol Slam Dunk Made RajonRondo Hold Ball RajonRondo Pass to PaulPierce Jump Shot RonArtest Foul Missed Free Throw 1 of 2 Made Free Throw 2 of 2 Missed PauGasol Rebound End Sample Output Lakers 2-1 Celtics Lakers PLAYER PTS OFF DEF REB AST STL BLK PF FGM-A 3PM-A FTM-A DerekFisher 0 0 0 0 0 0 0 0 0-0 0-0 0-0 KobeBryant 0 0 0 0 1 0 0 0 0-0 0-0 0-0 RonArtest 0 0 0 0 0 0 0 1 0-0 0-0 0-0 PauGasol 2 0 1 1 0 0 0 0 1-1 0-0 0-0 AndrewBynum 0 0 0 0 0 0 0 0 0-0 0-0 0-0 LamarOdom DNP - Coach's Decision MattBarnes DNP - Coach's Decision SteveBlake DNP - Coach's Decision ShannonBrown DNP - Coach's Decision LukeWalton DNP - Coach's Decision DerrickCaracter DNP - Coach's Decision DevinEbanks DNP - Coach's Decision Celtics PLAYER PTS OFF DEF REB AST STL BLK PF FGM-A 3PM-A FTM-A RajonRondo 0 0 0 0 0 0 0 0 0-0 0-0 0-0 RayAllen 0 0 0 0 0 0 0 0 0-0 0-0 0-0 PaulPierce 1 0 0 0 0 0 0 0 0-0 0-0 1-2 KevinGarnett 0 0 0 0 0 0 0 0 0-0 0-0 0-0 ShaquilleO'Neal 0 0 0 0 0 0 0 0 0-0 0-0 0-0 JeffGreen DNP - Coach's Decision VonWafer DNP - Coach's Decision GlenDavis DNP - Coach's Decision JermaineO'Neal DNP - Coach's Decision TroyMurphy DNP - Coach's Decision NenadKrstic DNP - Coach's Decision CarlosArroyo DNP - Coach's Decision

Crazy Basketball Fan 具体的实现

Problem Description Alex is a big fan of basketball and he enjoys watching NBA matches. But as he always has classes in the morning when the game is on, he has to read literal living broadcast with his cellphone instead of TV live. The living broadcast gives messages about who scores or who gets the rebound, etc. After watching a few games with his cellphone, Alex finds a problem. After each game, he wants to know the status of the players (score, rebound…) but the system always fails to give. So Alex decides to calculate himself. Can you help him? If one of your teammates is a crazy basketball fan, you should make him solve this problem because he will find it interesting while working on this problem. Input The first line of input contains an integer t (t<=10) indicate the number of cases. In each case, the first line contains the names of the two teams in the form of "A vs B", where A stands for the name of home team and B stands for the name of away team. The following 12 lines contain the name of the players play for the home team and another 12 lines contain the name of the players play for the away team. The first five players of each team will be the starters meaning they are on court when the game starts. All the names only contain letters from 'a' to 'z' and 'A' to 'Z' and ''' without space and the length of each name is no more than 20. All the players' names in one case will be different. Then a line contains an integer n (2<=n<=500) indicates the number of the messages given by the broadcast. The next n lines contain the messages, one message per line. The first line will always contain "Begin" and the last line will always contain "End". The game won't end during a shot or free throw, but may end at any other time. A message in other lines may be one of the following (x, x1 and x2 stand for players from the teams, m and M stand for numbers): Jump Ball x1 vs x2: this message will only be given on the second line right after "Begin". This means two players from different teams are jumping for the ball. This message will always be followed by "x Hold Ball" and x could be anyone. x Hold Ball: this message will be given if the ball is currently in no one's hand, which means: after jump ball or after a shot was made (including the last free throw) or after a shot was blocked or after timeout. x1 Pass to x2: this means the ball is passed from x1 to x2. x1 is deferent from x2 and they are from the same team. Layup/Slam Dunk/Hook Shot/Jump Shot/3pt Shot: the first four messages stand for an attempt for 2-point shot while the last message stand for an attempt for 3-point shot. These messages will only be given when someone is currently holding the ball. These messages may be followed by "Made"/"Missed"/"Blocked by x"/"x Foul". Made/Missed: If a shot was made and scored, "Made" will be given, otherwise "Missed". These two messages will be given right after a shot was attempted if the shot was not fouled or blocked. If the shot was fouled, these two messages will still be given right after "x Foul" to indicate whether the shot was made even with the foul. But if a shot was blocked, these messages will not be given since the shot is definitely missed. x Rebound: If a shot was missed, this message will be given to indicate who get the rebound (could be anyone from both teams). If someone gets the rebound, he holds the ball. Blocked by x: If a shot is blocked, this message will be given right after the message which indicates the shot. This message will always be followed by "x Hold Ball" and x could be anyone. A shot will only be blocked by a player from the opposite team with the shooter. x Foul: this message will be given when a player commit a foul to another player from the opposite team. There are two kind of foul. If this message is given right after the shot attempt, then this foul will lead to free throws. Otherwise this message will be followed by "x Hold Ball". Free Throw m of M: If a shot is fouled, the shooter will make free throws. If the fouled shot is made, then the shooter will only make one free throw. If it's missed and it's a 2-point shot, the shooter will make two free throws. If it's missed and it's a 3-point shot, the shooter will make three free throws. Each made free throw earns one point. In this message, m indicates the number of this free throw (start from 1) and M indicates the number of total free throws this player is going to attempt. Both m and M will be no bigger than 3 and m is no bigger than M. After each free throw there will be a message says "Made" or "Missed" to indicate whether the free throw is made or missed. If the last free throw is missed, just like normal shot, someone will get the rebound and if it's made, a player from the opposite team will hold the ball. No block could be made during the free throws. x Steal: If a player is now holding the ball, a player from the opposite team could steal the ball away. If someone steals the ball, he will hold it. x1 Substitution replaced by x2: this message means x1 is off court and replaced by x2. x1 and x2 are from the same team. This could only happen during timeout or before free throw or after a foul which doesn't lead to free throw. The player who is going to make a free throw won't be replaced. Before free throw means before any "Free Throw m of M" despite of m and M. Timeout: timeout could be called when someone is holding the ball. During timeout, substitution could be made. Timeout is ended with the message "x Hold Ball". It is guaranteed that all the messages are valid and follow the rules. The names of the players will not be the same with words like "rebound" and "block", etc. Actually all the names will be familiar to you if you watch NBA a lot. Output The first output line for each case will be "x1 n1-n2 x2", where x1 and x2 stand for the name of home team and away team and n1 and n2 stand for their total points. Then for each player from each team, calculate the number of his points, rebounds (including offensive and defensive), assists, steals, blocks and fouls. An assist is made when player x1 passes to player x2 and x2 makes a shot (2-pt or 3-pt) and then x1 gets the assist. A rebound is an offensive rebound when the shoot and the player who gets the rebound are from the same team (even the same player); otherwise it's a defensive rebound. Also you have to calculate the number of a player's made field goals (including 2-pt and 3-pt), attempted field goals (including 2-pt and 3-pt), made 3-pt shots, attempted 3-pt shots, made free throws and attempted free throws. Notice: if a shot is fouled and it's missed, it won't be counted as an attempt, but if it's fouled and made, it will be counted as an attempt and a made. The output form is shown in the sample output (PTS - points, OFF - offensive rebound, DEF - defensive rebound, REB - total rebound, AST - assist, STL - steal, BLK - block, PF - personal foul, FGM-A - field goal made and attempted, 3PM-A - 3-pt made and attempted, FTM-A - free throw made and attempted). There are 14 spaces before the word "PLAYER" and exact one space between each column. All the names and numbers are under their column and right alignment. The order of the players is the same with input. Home team first, then comes the away team. If a player didn't play at all (never on court), then you should print "DNP - Coach's Decision" 10 spaces after their names. Print a single line after each case. Sample Input 1 Lakers vs Celtics DerekFisher KobeBryant RonArtest PauGasol AndrewBynum LamarOdom MattBarnes SteveBlake ShannonBrown LukeWalton DerrickCaracter DevinEbanks RajonRondo RayAllen PaulPierce KevinGarnett ShaquilleO'Neal JeffGreen VonWafer GlenDavis JermaineO'Neal TroyMurphy NenadKrstic CarlosArroyo 17 Begin Jump Ball KevinGarnett vs PauGasol KobeBryant Hold Ball KobeBryant Pass to PauGasol Slam Dunk Made RajonRondo Hold Ball RajonRondo Pass to PaulPierce Jump Shot RonArtest Foul Missed Free Throw 1 of 2 Made Free Throw 2 of 2 Missed PauGasol Rebound End Sample Output Lakers 2-1 Celtics Lakers PLAYER PTS OFF DEF REB AST STL BLK PF FGM-A 3PM-A FTM-A DerekFisher 0 0 0 0 0 0 0 0 0-0 0-0 0-0 KobeBryant 0 0 0 0 1 0 0 0 0-0 0-0 0-0 RonArtest 0 0 0 0 0 0 0 1 0-0 0-0 0-0 PauGasol 2 0 1 1 0 0 0 0 1-1 0-0 0-0 AndrewBynum 0 0 0 0 0 0 0 0 0-0 0-0 0-0 LamarOdom DNP - Coach's Decision MattBarnes DNP - Coach's Decision SteveBlake DNP - Coach's Decision ShannonBrown DNP - Coach's Decision LukeWalton DNP - Coach's Decision DerrickCaracter DNP - Coach's Decision DevinEbanks DNP - Coach's Decision Celtics PLAYER PTS OFF DEF REB AST STL BLK PF FGM-A 3PM-A FTM-A RajonRondo 0 0 0 0 0 0 0 0 0-0 0-0 0-0 RayAllen 0 0 0 0 0 0 0 0 0-0 0-0 0-0 PaulPierce 1 0 0 0 0 0 0 0 0-0 0-0 1-2 KevinGarnett 0 0 0 0 0 0 0 0 0-0 0-0 0-0 ShaquilleO'Neal 0 0 0 0 0 0 0 0 0-0 0-0 0-0 JeffGreen DNP - Coach's Decision VonWafer DNP - Coach's Decision GlenDavis DNP - Coach's Decision JermaineO'Neal DNP - Coach's Decision TroyMurphy DNP - Coach's Decision NenadKrstic DNP - Coach's Decision CarlosArroyo DNP - Coach's Decision

SLAM ORB-SLAM2:Map Viewer画面不出现任何内容，卡死

 如图所示，这是别人的图片左侧有轨迹画面，我的只有右边的两个窗口，ORB-SLAM2:Map Viewer窗口没有任何画面，并且是卡死的，请问怎么回事？

机器人导航可以不用里程计么？

基于ROS操作系统的导航算法中，有没有不需要里程计就能规划路径的的导航算法。SLAM部分用cartographer解决了不用里程计制图的问题，但是怎么才能不用里程计导航呢。

激光雷达SLAM求助~望有经验的人指导一二~~

求助下，本人想用多线激光雷达做SLAM，刚接触，目前没有头绪，求助行家指导一下，学习的资料和方向有哪些？？？

在ros中跑slam数据集该怎么保存轨迹信息？

在ros里面跑euroc数据集，我打算保存运行的轨迹信息，在rviz上有显示，但我不知道该怎么样保存运行后的轨迹信息以用来与真值做比较。 求大佬zhi'dian

slam深度估计显示出的的depthmap全黑

初步接触slam，在做用cnn估计图片的深度的工作，发现在把估计出的dpthmap显示时，显示出的图片是全黑的： ``` depth,disparity = sess.run([model.depthmap_left,model.disparity_left[0]]) depth=depth.squeeze() disparity=disparity.squeeze() np.savetxt('./depthmap/{}.txt'.format(step),depth) misc.imsave('./depthmap/{}.png'.format(step),depth) np.savetxt('./dis/{}.txt'.format(step),disparity) misc.imsave('./dis/{}.png'.format(step),disparity) ``` 显示出的深度图 显示出的视差图 但是用np.savetxt('./depthmap/{}.txt'.format(step),depth) 读出的txt文件里深度值都挺大的，再用代码读depthmap的灰度值却又基本是0,两者完全不符合，它显示图片的原理是什么，为什么depthmap是全黑的呢？

《视觉SLAM十四讲》第5讲PCL的以命令行编译的问题 ？

困扰好几天的问题求解。！！！！！ cmake 编译之后的结果  make 编译后的结果  程序运行显示的错误如下  声明：栈空间大小为8M. 系统为ubuntu18.04

终于明白阿里百度这样的大公司，为什么面试经常拿ThreadLocal考验求职者了

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