# 2016q3 Homework1 (phonebook)
contributed by <`SarahCheng`>

github:
https://github.com/SarahYuHanCheng/phonebook.git
### Reviewed by <`snoopy831002`>
* 可以在github網站創立好repo之後再clone到本地端會比較方便喔
* 改良之後的cache miss還是太高(74%?)

> 好的,謝謝你！再用hash table試試

## 開發記錄
* 9/24 watch the video, register accounts
* 9/25 install lubuntu
>> 不需要在內文標注「日期」，HackMD 會追蹤，應該紀錄「主題導向」的實驗和參考資料 [name=jserv]

* 9/26 problem:
* wifi setting
* ~~螢幕畫面截取~~
* ~~linux cmd instruction不熟~~
* problem:
* $make 沒有出現"[sudo] password for"
* $make plot沒有runtime.png,只有script/runtime.gp
>之後有了

* $ lscpu | grep cache沒有反應..
>$ lscpu ~~| grep cache~~即可[time=Tue, Sep 27, 2016 3:37 PM][color=#bdd9f9]

* ~~用astyle沒反應~~：因為少了空白
`astyle --style=kr --indent=spaces=4 --indent-switches --suffix=none`空格`*.[ch]`
> 需要解釋「沒反應」為何 [name=jserv]

* reference:
* [linux指令](http://jdev.tw/blog/3599/linux-terminal-commands-and-shortcuts)
* [螢幕截取-shutter](https://blog.gtwang.org/linux/linux-screenshot-program-shutter/)
* [makefile裡GCC](http://www.cmlab.csie.ntu.edu.tw/~daniel/linux/gcc.html)
* [TempoJiJi](https://hackmd.io/MYUwzMCGCckAwFoBMcAmB2BAWa1UMmCIRAEYkA2MddEADjmCyA==?view)同學的開發記錄
* [ruby0109](https://github.com/ruby0109/phonebook/blob/master/phonebook_hash.c)同學的開發記錄
* [c14006078](https://hackmd.io/MYNgnCDsCsYEwFoAmInQQFngMwQQwCM5dI88BmAU3LnIEYlsAGIA#)同學的開發記錄

## 開發環境
* CPU: Intel(R) Core(TM) i7-3520M cpu @ 2.90GHz
* MEM: 125GB
* Cache:
* L1d cache: 32K
* L1i cache: 32K
* L2 cache: 256K
* L3 cache: 4096K

使用 `lscpu` 和 `sudo lshw` 可看到硬體資訊

## 修改結構大小降低cache miss
steps:
1.修改`phonebook_opt.h`如下圖

typedef struct __PHONE_BOOK_DETAILS {
    char firstName[16];
    char email[16];
    char phone[10];
    char cell[10];
    char addr1[16];
    char addr2[16];
    char city[16];
    char state[2];
    char zip[5];
} Details;

typedef struct __PHONE_BOOK_ENTRY {
    char lastName[MAX_LAST_NAME_SIZE];
    struct __PHONE_BOOK_ENTRY *pNext;
    Details *details;
} entry;

2.`phonebook_opt.c`的append()和findName()複製orig版本
3.記得解開 the comment ` #define OPT 1`
4.清空cache:

$echo 1 | sudo tee /proc/sys/vm/drop_caches

5.make plot 即得下列資訊

size of entry : 128 bytes
execution time of append() : 0.087335 sec
execution time of findName() : 0.005850 sec

 Performance counter stats for './phonebook_orig' (100 runs):

         1,426,148      cache-misses              #   82.108 % of all cache refs      ( +-  0.48% )  (74.11%)
         1,736,927      cache-references                                              ( +-  0.54% )  (74.39%)
       305,721,382      instructions              #    1.47  insns per cycle          ( +-  0.18% )  (77.20%)
       207,828,652      cycles                                                        ( +-  0.24% )  (76.70%)

       0.068671339 seconds time elapsed                                          ( +-  1.91% )


size of entry : 24 bytes
execution time of append() : 0.036632 sec
execution time of findName() : 0.002973 sec

 Performance counter stats for './phonebook_opt' (100 runs):

           232,097      cache-misses              #   74.079 % of all cache refs      ( +-  0.37% )  (74.46%)
           313,312      cache-references                                              ( +-  0.51% )  (74.79%)
       278,824,752      instructions              #    1.75  insns per cycle          ( +-  0.28% )  (76.75%)
       159,089,222      cycles                                                        ( +-  0.28% )  (77.42%)

       0.050675378 seconds time elapsed                                          ( +-  1.75% )


 Performance counter stats for './phonebook_orig' (100 runs):

         1,469,675      cache-misses              #   81.589 % of all cache refs      ( +-  0.61% )
         1,801,320      cache-references                                              ( +-  0.60% )
       310,382,365      instructions              #    1.45  insns per cycle          ( +-  0.01% )
       214,099,227      cycles                                                        ( +-  0.17% )

       0.070388042 seconds time elapsed                                          ( +-  2.18% )

           235,670      cache-misses              #   79.971 % of all cache refs      ( +-  0.22% )
           294,695      cache-references                                              ( +-  0.21% )
       288,137,012      instructions              #    1.78  insns per cycle          ( +-  0.00% )
       162,238,829      cycles                                                        ( +-  0.08% )

## fgets

###### Use fgets characteristic to delay the replacing '\n' with '\0'.

利用 fgets的特性，man 完就會發現它會在讀到 newline 或是 EOF停下來並且在他們後面會多種一個 '\0'，接著的 code 就是把 newline 變成 '\0'，我們延後替換 newline，我操作只比較前面的長度，真的找到了再把 newline 換掉即可。

* main.c

while (fgets(line, sizeof(line), fp))
e = append(line, e);

* phonebook_opt.c

/* because the assert test, we can’t modify the strcut*/
if (strncasecmp(lastname, pHead->lastName, len) == 0 &&
    (pHead->lastName[len] == ’\n’ ||
     pHead->lastName[len] == ’\0’)) {
    pHead->lastName[len] = ’\0’;
   return pHead;

原本的程式是將字典直接建好，這邊我們先建檢索，等到findName找到時我們再去補上他的資料，這樣也能減少 append()。

* Q1:`error: stray ‘342’ in program`
> A:ascii characters missing，程式碼用複製貼上，導致'\n'的引號格式不符

* Q2:Assertion failed，還不知道怎解決

size of entry : 24 bytes
phonebook_opt: main.c:89: main: Assertion `0 == strcmp(findName(input, e)->lastName, "zyxel")' failed.
./phonebook_opt: 已經終止


6.用`astyle --style=kr --indent=spaces=4 --indent-switches --suffix=none *.[ch]`
7.`ln -sf ../../scripts/pre-commit.hook .git/hooks/pre-commit`

## Hash

不明原因

error: conflicting types for ‘hashAppend’
    int *hashAppend(char *lastName, hashTable *ht)

[無解,也許是編譯警告太多了](http://www.wnqzw.com/article/9823.html)

## GIT
step:

1.[指令參考](http://fireqqtw.logdown.com/posts/196392-git-casually-notes#reset)
2.[本機與github同步](http://wiki.csie.ncku.edu.tw/github)

> 貼id_rsa.pub所有內容到github上key的設定

2.若出現`fatal: Not a git repository (or any of the parent directories): .git`，因為還沒有.git目錄，要先`git init`
3.

 fatal: The current branch master has no upstream branch.
To push the current branch and set the remote as upstream, use

    git push --set-upstream phonebook master

###### tags: `sarah`,`phonebook`