Linux x64 下 Matlab R2013a 300 kb 脚本文件调试的 CPU 占用过高问题的解决办法

(1) 系统+软件版本

     CentOS 6.5 (Final), 64 位，内核initramfs-2.6.32-431.5.1.el6.x86_64，

     MATLAB Version: 8.1.0.604 (R2013a)
     Java 1.6.0_17-b04 with Sun Microsystems Inc. Java HotSpot(TM) 64-Bit Server VM mixed mode

(2) 问题描述

     通常在这个环境下,小文件的代码都可以调试通过.

     最近,把所有函数集合到一个M文件(332.4 kb),只是简单地设置了几个断点, 运行到断点位置再停止运行, cpu和内存占用都还算正常.

     但接下来对m文件的编辑就开始变得非常慢, 甚至是只添加几个单词就会卡住, 一直没有响应, 内存占用不变, 而1/4核CPU的占用高达100%, 只能从系统监视器里杀死进程. 

     我猜想, Matlab对M文件大小的支持,是不是非常有限? 子函数版本太多也是罪过,想着集成起来可以方便调用和标注,没想到弄巧成拙了...

(3) 解决办法

找到两个解决办法.

一是使用 '-singleCompThread' 参数启动matlab. 亲测可用. 调试编辑都和原来基本一样, 不再卡顿了. 这要感谢水木网友 @RSVP 的耐心解答.

[usr@usr ~]$ matlab -help

    Usage:  matlab [-h|-help] | [-n | -e]
                   [-arch | v=variant | v=arch/variant]
                   [-c licensefile] [-display Xdisplay | -nodisplay]
                   [-nosplash] [-mwvisual visualid] [-debug] [-softwareopengl]
                   [-desktop | -nodesktop | -nojvm]
                   [-r MATLAB_command] [-logfile log]
                   [-Ddebugger [options]]

    -h|-help             - Display arguments.
    -n                   - Display final environment variables,
                           arguments, and other diagnostic
                           information. MATLAB is not run.
    -e                   - Display ALL the environment variables and
                           their values to standard output. MATLAB
                           is not run. If the exit status is not
                           0 on return then the variables and values
                           may not be correct.
    -arch                - Start MATLAB assuming architecture arch.
    v=variant            - Start the version of MATLAB found
                           in bin/glnxa64/variant instead of bin/glnxa64.
    v=arch/variant       - Start the version of MATLAB found
                           in bin/arch/variant instead of bin/glnxa64.
    -c licensefile       - Set location of the license file that MATLAB
                           should use.  It can have the form port@host or
                           be a colon separated list of license files.
                           The LM_LICENSE_FILE and MLM_LICENSE_FILE
                           environment variables will be ignored.
    -display Xdisplay    - Send X commands to X server display, Xdisplay.
    -nodisplay           - Do not display any X commands. The MATLAB
                           desktop will not be started. However, unless
                           -nojvm is also provided the Java virtual machine
                           will be started.
    -nosplash            - Do not display the splash screen during startup.
    -mwvisual visualid   - The default X visual to use for figure windows.
    -debug               - Provide debugging information especially for X
                           based problems.
    -desktop             - Allow the MATLAB desktop to be started by a
                           process without a controlling terminal. This is
                           usually a required command line argument when
                           attempting to start MATLAB from a window manager
                           menu or desktop icon.
    -nodesktop           - Do not start the MATLAB desktop. Use the current
                           terminal for commands. The Java virtual machine
                           will be started.
    -singleCompThread    - Limit MATLAB to a single computational thread. 
                           By default, MATLAB makes use of the multithreading 
                           capabilities of the computer on which it is running.
    -nojvm               - Shut off all Java support by not starting the
                           Java virtual machine. In particular the MATLAB
                           desktop will not be started.
    -jdb [port]          - Enable remote Java debugging on port (default 4444)
    -r MATLAB_command    - Start MATLAB and execute the MATLAB_command.
    -logfile log         - Make a copy of any output to the command window
                           in file log. This includes all crash reports.
    -Ddebugger [options] - Start debugger to debug MATLAB.
    -nouserjavapath      - Ignore custom javaclasspath.txt and javalibrarypath.txt files.

二是使用外部编辑器 Emacs 来编辑和调试. 调试采用 matlab-shell mode, 稍微复杂一些, 传统的快捷键都不怎么能用, 只能用命令设置断点和运行, 涉及到的命令有: dbstop & dbstatus & dbcont & dbquit 等, 可参阅这篇博客<MATLAB的简单debug功能>. 在调试过程中编辑脚本也没问题, matlab 占用也小. 有关 Emacs 多窗口之间切换的快捷键可以参考 学习Emacs系列教程（十）：多窗口.

全文完.