Directory

大量文件的目錄結構

  • December 13, 2020

我有數百萬個文件,其文件名是內容的 SHA256 雜湊值。由於性能原因,我不想將它們儲存在單個目錄中。我的想法是建立基於 SHA256 雜湊的目錄結構——例如,目錄./A/A/A/A/A將包含所有以 AAAAA 開頭的文件。

例如,一個雜湊是AAAAAFF02F52AA70E57EA3FD67019A7A919D373915AA30393936D9CC

有沒有辦法自動創建這樣的目錄結構(具有定義的子目錄級別 - 即 5 或 10)?如何自動創建此目錄結構?

這是一個解決您的問題的框架,您可能需要根據自己的需要進行定制。這裡有相當多的調試和測試文件創建。首先是測試日誌,然後是腳本。歡迎查詢。

我假設您的文件數約為 1600 萬(實際上是 16 * 1024 * 1024)。所以我選擇了一棵樹,第一級有 256 個目錄,每個第二級有 256 個目錄(所以該級別有 65,536 個目錄),然後每個目錄的文件平均為 256 個。如果您希望採用 4 或 5 級方案,則更改很小(詢問是否不明顯)。

awk用來將 sha256 名稱轉換為mv命令,並將它們通過管道傳輸到bash(距離末尾約 2 行)。我建議您刪除,| bash直到您確定命令符合您的期望。還有一些清理行 ( rm -rf) 和一些您希望清理或註釋掉的調試 (ls和)。find

該腳本在所有數百萬個文件所在的目錄中執行,"Tree"變數是整個樹所在的位置。這需要在同一個文件系統上,因此 mv 只需要更改每個文件的目錄條目:如果源和目標位於不同的文件系統上,則 mv 將改為像 cp 一樣,程序將“永遠”執行。

這是完整的測試執行:

/home/paul/SandBox/Toys/dirTree
total 8
-rwxr-xr-x 1 paul paul 1841 Dec 12 23:59 myTree
-rw-r--r-- 1 paul paul   32 Dec 12 23:59 myTree.log
Making test files ...
total 544
-rw-r--r-- 1 paul paul  17545 Dec 12 23:59 4E8A34A5010C507ADF81E3D9EEC6330A9E866D3B70857111D3A9DF5C5008BA9D
-rw-r--r-- 1 paul paul  90655 Dec 12 23:59 590A853F3C97C05BB55BBBDFBA988210066807C188E54B78F340F01DD48C0AF5
-rw-r--r-- 1 paul paul   2685 Dec 12 23:59 5B02D3A74A2E4B433D0C7DEE57446460CCE6661E3CE59918B5243B903E3358A6
-rw-r--r-- 1 paul paul   2051 Dec 12 23:59 6F48C65B219CA78B8C7FF03F12A8E27E1A298A541481E9B3C86645B622DCB5B1
-rw-r--r-- 1 paul paul  13545 Dec 12 23:59 8FED5B546352BF30E3B98E7EB8EB916DA5E2814B4227461F01173547263BB257
-rw-r--r-- 1 paul paul 311346 Dec 12 23:59 A8BCA57679FE42C2902D2AE70804C4C93088079B167BC99A7827295FFB34D32E
-rw-r--r-- 1 paul paul   2092 Dec 12 23:59 B31470EC1AF3204CF2327F12A48296F8161B51E3C30679EFA71E65AA882DCED4
-rw-r--r-- 1 paul paul   4602 Dec 12 23:59 C2BFA9351040ABA8F36990D0C3E3E32F70F2E94EF8D05AEDC5EE3B32270953D3
-rw-r--r-- 1 paul paul   7687 Dec 12 23:59 C9FA54EEF557DE7B67B66A145CCC0D65037117F0EDFF8EFCE694B56C4A6F7FEB
-rw-r--r-- 1 paul paul  71752 Dec 12 23:59 D3040C6348CB758498988DA5FAF086666553B27CFB7E591B5E7616C3E8373068
-rwxr-xr-x 1 paul paul   1841 Dec 12 23:59 myTree
-rw-r--r-- 1 paul paul    204 Dec 12 23:59 myTree.log

real    0m1.992s
user    0m2.196s
sys 0m0.296s
Making directory tree ...
/home/paul/SandBox/Toys/dirTree/sha256
256
65536
  262748      4 drwxr-xr-x   2 paul     paul         4096 Dec 12 23:59 ./01/B4
  262811      4 drwxr-xr-x   2 paul     paul         4096 Dec 12 23:59 ./01/F3
  262752      4 drwxr-xr-x   2 paul     paul         4096 Dec 12 23:59 ./01/B8
  262644      4 drwxr-xr-x   2 paul     paul         4096 Dec 12 23:59 ./01/4C

real    3m47.220s
user    0m42.700s
sys 0m32.900s
  135626     72 -rw-r--r--   1 paul     paul        71752 Dec 12 23:59 sha256/D3/04/D3040C6348CB758498988DA5FAF086666553B27CFB7E591B5E7616C3E8373068
  135639    308 -rw-r--r--   1 paul     paul       311346 Dec 12 23:59 sha256/A8/BC/A8BCA57679FE42C2902D2AE70804C4C93088079B167BC99A7827295FFB34D32E
  135641     20 -rw-r--r--   1 paul     paul        17545 Dec 12 23:59 sha256/4E/8A/4E8A34A5010C507ADF81E3D9EEC6330A9E866D3B70857111D3A9DF5C5008BA9D
  133634      4 -rw-r--r--   1 paul     paul         2685 Dec 12 23:59 sha256/5B/02/5B02D3A74A2E4B433D0C7DEE57446460CCE6661E3CE59918B5243B903E3358A6
  135640     92 -rw-r--r--   1 paul     paul        90655 Dec 12 23:59 sha256/59/0A/590A853F3C97C05BB55BBBDFBA988210066807C188E54B78F340F01DD48C0AF5
  135625      8 -rw-r--r--   1 paul     paul         7687 Dec 12 23:59 sha256/C9/FA/C9FA54EEF557DE7B67B66A145CCC0D65037117F0EDFF8EFCE694B56C4A6F7FEB
  135642     16 -rw-r--r--   1 paul     paul        13545 Dec 12 23:59 sha256/8F/ED/8FED5B546352BF30E3B98E7EB8EB916DA5E2814B4227461F01173547263BB257
  135624      4 -rw-r--r--   1 paul     paul         2051 Dec 12 23:59 sha256/6F/48/6F48C65B219CA78B8C7FF03F12A8E27E1A298A541481E9B3C86645B622DCB5B1
  135628      4 -rw-r--r--   1 paul     paul         2092 Dec 12 23:59 sha256/B3/14/B31470EC1AF3204CF2327F12A48296F8161B51E3C30679EFA71E65AA882DCED4
  135630      8 -rw-r--r--   1 paul     paul         4602 Dec 12 23:59 sha256/C2/BF/C2BFA9351040ABA8F36990D0C3E3E32F70F2E94EF8D05AEDC5EE3B32270953D3

real    0m2.118s
user    0m0.528s
sys 0m1.520s

這是腳本:

#! /bin/bash

Tree="sha256"

#.. Fake some test files from man pages, renamed with their own sha256.

mkFile () {

   local Fn
   local Awk='{ printf ("%s\n", toupper ($(NF))); }'

   man -s 1 "${1}" > Man
   Fn=$( openssl dgst -sha256 Man | awk "${Awk}" )
   mv Man "${Fn}"
}

#.. Make a directory tree for the first 4 hex characters of any name,
#.. such that files 7BC12A13... go into ./7B/C1.

mkDirs () {

   local a b c d
   for a in {0..9} {A..F}; do
       for b in {0..9} {A..F}; do
           for c in {0..9} {A..F}; do
               for d in {0..9} {A..F}; do
                   mkdir -p ./${a}${b}/${c}${d}
               done
           done
       done
   done
}

#.. Move all files in the current directory that have sha256-type names
#.. into their appropriate directory.

mvFiles () {

   local Awk='
BEGIN {
   FS = "/";
   cmd = "mv -t \047%s/%s/%s\047 \047%s\047\n";
}
length ($NF) == 64 && $NF ~ /^[[:xdigit:]]*$/ {
   printf (cmd, Tree, substr ($NF, 1, 2), substr ($NF, 3, 2), $NF);
}
'
   awk -v Tree="${Tree}" -f <( printf '%s' "${Awk}" ) -
}

#.. Tests.

   #.. Nothing up my sleeves.
   pwd
   ls -l

   #.. Make some test files.
   [ x ] && time (
       echo "Making test files ..."
       for tx in cut cat ls find wc dd bash awk vi dc; do
           mkFile "${tx}"
       done
       ls -l
   )

   #.. Make a directory tree.
   [ x ] && time (
       echo "Making directory tree ..."
       rm -rf ${Tree}
       mkdir -p ${Tree}
       cd ${Tree} || exit

       pwd
       mkDirs
       ls -d * | wc -l
       ls -d */* | wc -l
       find . -ls | tail -n +1299 | head -n 4
   )

   #.. Move all the local sha256 files into the tree.
   [ x ] && time (
       find . -maxdepth 1 -type f | mvFiles "${Tree}" | bash
       find "${Tree}" -type f -ls
   )

引用自:https://unix.stackexchange.com/questions/624009