note - The Balanced ScoreCard

平衡計分卡不能為企業創造策略，但能幫組織有效執行策略。平衡計分卡以組織的共同願景與戰略為內核，將公司的願景與戰略轉化為下屬各責任部門(如各事業部)在財務(Financial)、顧客(Customer)、內部流程(Internal Processes)、創新與學習(Innovation&Learning)等四個方面的系列具體目標(即成功的因素)，並設置相應的四張計分卡，其基本框架見下圖：

優點：
企業向來以財務數字做為績效衡量的標準，但無論是業績目標或營收、投資報酬率等，都是反映過去行動所獲致的成果；簡單說，財務數字衡量的是「過去的績效」，是一種「落後指標」，而非創造未來績效的指引。
平衡計分卡的理念在於：在財務衡量（落後指標）之外，積極找出能夠創造未來財務成果的「績效驅動因素」（performance driver），也就是相較財務成果而言的「領先指標」，例如顧客滿意度、高效率的流程、員工能力、士氣等，讓「績效衡量制度」能與「策略」配合一致。
平衡計分卡不僅是一種管理手段，也體現了一種管理思想，就是：只有量化的指標才是可以考核的，必須將要考核的指標進行量化

缺點：
平衡計分卡中有一些條目是很難解釋清楚或者是衡量出來的。財務指標當然不是問題，而非財務指標往往很難去建立起來。

參考資料：
• http://wiki.mbalib.com/zh-tw/%E5%B9%B3%E8%A1%A1%E8%AE%A1%E5%88%86%E5%8D%A1, 平衡計分卡
• https://www.managertoday.com.tw/articles/view/2489, 5分鐘！了解「平衡計分卡」

Using gdbserver to debug MDM9xxx

openembedded提供了一個良好的gdb環境，設定步驟如下。

brook@vista:/home/brook/apps_proc/poky/build$ tar zxvf tmp-glibc/deploy/images/mdm9607/machine-image-mdm9607-dbg.tar.gz
./
./var/
./var/lib/
./var/lib/opkg/
./var/lib/opkg/info/
...

brook@vista:/home/brook/apps_proc/poky/build$ mv usr/lib/.debug/* usr/lib/
brook@vista:/home/brook/apps_proc/poky/build$ mv lib/.debug/* lib

brook@vista:/home/brook/apps_proc/poky/build$ ln -s libconfig.so.9.2.0 usr/lib/libconfig.so.9
...

brook@vista:/home/brook/apps_proc/poky/build$ ln -s libpthread-2.22.so lib/libpthread.so.0
brook@vista:/home/brook/apps_proc/poky/build$ ln -s librt-2.22.so lib/librt.so.1
brook@vista:/home/brook/apps_proc/poky/build$ ln -s libm-2.22.so lib/libm.so.6
brook@vista:/home/brook/apps_proc/poky/build$ ln -s libc-2.22.so lib/libc.so.6
brook@vista:/home/brook/apps_proc/poky/build$ ln -s ld-2.22.so lib/ld-linux.so.3
brook@vista:/home/brook/apps_proc/poky/build$ ln -s libdl-2.22.so lib/libdl.so.2
...

brook@vista:/home/brook/apps_proc/poky/build/tmp-glibc/work/armv7a-vfp-neon-oe-linux-gnueabi/myprog/git-r0/build/src$ adb push myprog /usr/bin/myprog

brook@vista:/home/brook/apps_proc/poky/build/tmp-glibc/work/armv7a-vfp-neon-oe-linux-gnueabi/myprog/git-r0/build/src$ adb shell
sh-3.2# gdbserver :2345 /usr/bin/myprog
Process /usr/bin/myprog created; pid = 9035
Listening on port 2345

接著host端就可以開啟GDB來debug了

brook@vista:/home/brook/apps_proc/poky/build/tmp-glibc/work/armv7a-vfp-neon-oe-linux-gnueabi/myprog/git-r0/build/src$ arm-oe-linux-gnueabi-gdb myprog 
GNU gdb (GDB) 7.10.1
Copyright (C) 2015 Free Software Foundation, Inc.
...
Reading symbols from myprog...done.
(gdb) set sysroot /home/brook/apps_proc/poky/build/
(gdb) target remote 10.0.0.1:2345
Remote debugging using 10.0.0.1:2345
Reading symbols from /home/brook/apps_proc/poky/build//lib/ld-linux.so.3...done.
0xb6fceac0 in ?? ()
(gdb) b main
Breakpoint 1 at 0x7f5595ac: file /home/brook/apps_proc/poky/build/tmp-glibc/work/armv7a-vfp-neon-oe-linux-gnueabi/myprog/git-r0/src/main.c, line 207.
(gdb) c
Continuing.

Breakpoint 1, main (argc=1, argv=0xbefffdf4)
    at /home/brook/apps_proc/poky/build/tmp-glibc/work/armv7a-vfp-neon-oe-linux-gnueabi/myprog/git-r0/src/main.c:207
207     {
(gdb) set sysroot /home/brook/apps_proc/poky/build
warning: .dynamic section for "/home/brook/apps_proc/poky/build/lib/libpthread.so.0" is not at the expected address (wrong library or version mismatch?)
warning: .dynamic section for "/home/brook/apps_proc/poky/build/lib/libm.so.6" is not at the expected address (wrong library or version mismatch?)
warning: .dynamic section for "/home/brook/apps_proc/poky/build/lib/libc.so.6" is not at the expected address (wrong library or version mismatch?)
Use the "info sharedlibrary" command to see the complete listing.
Do you need "set solib-search-path" or "set sysroot"?
Reading symbols from /home/brook/apps_proc/poky/build/usr/lib/libconfig.so.9...done.
Reading symbols from /home/brook/apps_proc/poky/build/lib/libpthread.so.0...done.
Reading symbols from /home/brook/apps_proc/poky/build/lib/librt.so.1...done.
Reading symbols from /home/brook/apps_proc/poky/build/lib/libm.so.6...done.
Reading symbols from /home/brook/apps_proc/poky/build/lib/libc.so.6...done.
Reading symbols from /home/brook/apps_proc/poky/build/lib/libdl.so.2...done.
(gdb) info share
From        To          Syms Read   Shared Object Library
0x7473e7c0  0x7475a328  Yes         /home/brook/apps_proc/poky/build/lib/ld-linux.so.3
0xb6fc42d0  0xb6fca6e0  Yes         /home/brook/apps_proc/poky/build/usr/lib/libconfig.so.9
0xb6ebc210  0xb6ecb4e8  Yes         /home/brook/apps_proc/poky/build/lib/libpthread.so.0
0xb6ea2720  0xb6ea6034  Yes         /home/brook/apps_proc/poky/build/lib/librt.so.1
0xb6e28bf0  0xb6e5ac20  Yes         /home/brook/apps_proc/poky/build/lib/libm.so.6
0xb6ced280  0xb6dee638  Yes         /home/brook/apps_proc/poky/build/lib/libc.so.6
0xb6cc3928  0xb6cc4870  Yes         /home/brook/apps_proc/poky/build/lib/libdl.so.2

確認所有symbol都有找到之後, 就可以開始debug之旅了.

note for "The Art of Readable Code" - CH13 Writing Less Code

The most readable code is no code at all.

Programmer最重要的技能之一就是知道哪些code不用寫，因為寫出來就要測試&維護，越小的程式碼越容易被維護，coupling程度越低越好，最好彼此獨立，有幾個方向:

1. Create as much generic “utility” code as possible to remove duplicated code. (See Chapter 10, Extracting Unrelated Subproblems.)
2. Remove unused code or useless features. (See the following sidebar.)
3. Keep your project compartmentalized into disconnected subprojects.
4. Generally, be conscious of the “weight” of your codebase. Keep it light and nimble.

Be Familiar with the Libraries Around You

每隔一段時間應該要花一下時間，讀一下你的 standard library，目的在於能對standard library的API有概念，以便在coding時能聯想到,並大量且反覆地使用這些library。

參考資料:
• The Art of Readable Code