linux技巧:一次刪除一百萬個檔案的最快方法
最初的評估
昨天,我看到一個非常有趣的刪除一個目錄下的海量檔案的方法。這個方法來自http://www.quora.com/How-can-someone-rapidly-delete-400-000-files裡的Zhenyu Lee。
他沒有使用find 或 xargs,他很有創意的利用了rsync的強大功能,使用rsync –delete將目標資料夾以一個空資料夾來替換。之後,我做了一個實驗來比較各種方法。讓我吃驚的是,Lee的方法比其它的快的多。下面就是我的測評。
環境:
CPU: Intel(R) Core(TM)2 Duo CPU E8400 @ 3.00GHz
MEM: 4G
HD: ST3250318AS: 250RPG/7200%
Deletion Time
rsync -a –delete empty/ s1/ 1000000 6m50.638s
find s2/ -type f -200
find s3/ -type f | xargs -L 100 rm 1000000 83m36.851s
find s4/ -type f | xargs -L 100 -P 100 rm 1000000 78m4.658s
使用 –delete 和 –exclude,你可以選擇性刪除符合條件的檔案。還有一點,當你需要保留這個目錄做其它用處時,這種方法是再適合不過了。 重新評估幾天前,Keith-Winstein在回覆Quora上的這個貼文時說我之前的測評無法複製,因為操作的時間持續的太久。我澄清一下,這些數據過大,可能是因為我的計算機在過去的幾年裡做的事太多,測評中可能存在一些檔案系統錯誤。但我不確定是這些原因。現在好了,我弄了一天比較新的計算機,把測評再做一次。這次我使用/usr/bin/time,它能提供更詳細的資訊。下面就是新的結果。 (每次都是1000000個檔案。每個檔案的體積都是0。) CommandElapsedSystem Time%CPUEapsedSystem Time%CPU🜎 -a –delete empty/ a 10.60 1.31 95 106/22 find b/ -type f -delete 28.51121 find c/ -type f | xargs -L 100 rm 41.69 20.60 54 37048/15074find d/ -type f | xargs -L 100 -P 100 rm 34.32 27.82 89 929897/21720 89 929897/21720 89 929897/21720 89 929897/21720 89 929897/21720 89 中時 f 47 15134/11 原輸出
# method 1 ~/test $ /usr/bin/time -v rsync -a --delete empty/ a/ Command being timed: "rsync -a --delete empty/ a/" User time (seconds): 1.31 System time (seconds): 10.60 Percent of CPU this job got: 95% Elapsed (wall clock) time (h:mm:ss or m:ss): 0:12.42 Average shared text size (kbytes): 0 Average unshared data size (kbytes): 0 Average stack size (kbytes): 0 Average total size (kbytes): 0 Maximum resident set size (kbytes): 0 Average resident set size (kbytes): 0 Major (requiring I/O) page faults: 0 Minor (reclaiming a frame) page faults: 24378 Voluntary context switches: 106 Involuntary context switches: 22 Swaps: 0 File system inputs: 0 File system outputs: 0 Socket messages sent: 0 Socket messages received: 0 Signals delivered: 0 Page size (bytes): 4096 Exit status: 0 # method 2 Command being timed: "find b/ -type f -delete" User time (seconds): 0.41 System time (seconds): 14.46 Percent of CPU this job got: 52% Elapsed (wall clock) time (h:mm:ss or m:ss): 0:28.51 Average shared text size (kbytes): 0 Average unshared data size (kbytes): 0 Average stack size (kbytes): 0 Average total size (kbytes): 0 Maximum resident set size (kbytes): 0 Average resident set size (kbytes): 0 Major (requiring I/O) page faults: 0 Minor (reclaiming a frame) page faults: 11749 Voluntary context switches: 14849 Involuntary context switches: 11 Swaps: 0 File system inputs: 0 File system outputs: 0 Socket messages sent: 0 Socket messages received: 0 Signals delivered: 0 Page size (bytes): 4096 Exit status: 0 # method 3 find c/ -type f | xargs -L 100 rm ~/test $ /usr/bin/time -v ./delete.sh Command being timed: "./delete.sh" User time (seconds): 2.06 System time (seconds): 20.60 Percent of CPU this job got: 54% Elapsed (wall clock) time (h:mm:ss or m:ss): 0:41.69 Average shared text size (kbytes): 0 Average unshared data size (kbytes): 0 Average stack size (kbytes): 0 Average total size (kbytes): 0 Maximum resident set size (kbytes): 0 Average resident set size (kbytes): 0 Major (requiring I/O) page faults: 0 Minor (reclaiming a frame) page faults: 1764225 Voluntary context switches: 37048 Involuntary context switches: 15074 Swaps: 0 File system inputs: 0 File system outputs: 0 Socket messages sent: 0 Socket messages received: 0 Signals delivered: 0 Page size (bytes): 4096 Exit status: 0 # method 4 find d/ -type f | xargs -L 100 -P 100 rm ~/test $ /usr/bin/time -v ./delete.sh Command being timed: "./delete.sh" User time (seconds): 2.86 System time (seconds): 27.82 Percent of CPU this job got: 89% Elapsed (wall clock) time (h:mm:ss or m:ss): 0:34.32 Average shared text size (kbytes): 0 Average unshared data size (kbytes): 0 Average stack size (kbytes): 0 Average total size (kbytes): 0 Maximum resident set size (kbytes): 0 Average resident set size (kbytes): 0 Major (requiring I/O) page faults: 0 Minor (reclaiming a frame) page faults: 1764278 Voluntary context switches: 929897 Involuntary context switches: 21720 Swaps: 0 File system inputs: 0 File system outputs: 0 Socket messages sent: 0 Socket messages received: 0 Signals delivered: 0 Page size (bytes): 4096 Exit status: 0 # method 5 ~/test $ /usr/bin/time -v rm -rf f Command being timed: "rm -rf f" User time (seconds): 0.20 System time (seconds): 14.80 Percent of CPU this job got: 47% Elapsed (wall clock) time (h:mm:ss or m:ss): 0:31.29 Average shared text size (kbytes): 0 Average unshared data size (kbytes): 0 Average stack size (kbytes): 0 Average total size (kbytes): 0 Maximum resident set size (kbytes): 0 Average resident set size (kbytes): 0 Major (requiring I/O) page faults: 0 Minor (reclaiming a frame) page faults: 176 Voluntary context switches: 15134 Involuntary context switches: 11 Swaps: 0 File system inputs: 0 File system outputs: 0 Socket messages sent: 0 Socket messages received: 0 Signals delivered: 0 Page size (bytes): 4096 Exit status: 0

熱AI工具

Undresser.AI Undress
人工智慧驅動的應用程序,用於創建逼真的裸體照片

AI Clothes Remover
用於從照片中去除衣服的線上人工智慧工具。

Undress AI Tool
免費脫衣圖片

Clothoff.io
AI脫衣器

Video Face Swap
使用我們完全免費的人工智慧換臉工具,輕鬆在任何影片中換臉!

熱門文章

熱工具

記事本++7.3.1
好用且免費的程式碼編輯器

SublimeText3漢化版
中文版,非常好用

禪工作室 13.0.1
強大的PHP整合開發環境

Dreamweaver CS6
視覺化網頁開發工具

SublimeText3 Mac版
神級程式碼編輯軟體(SublimeText3)

Linux系統的五個基本組件是:1.內核,2.系統庫,3.系統實用程序,4.圖形用戶界面,5.應用程序。內核管理硬件資源,系統庫提供預編譯函數,系統實用程序用於系統管理,GUI提供可視化交互,應用程序利用這些組件實現功能。

vscode 內置終端是一個開發工具,允許在編輯器內運行命令和腳本,以簡化開發流程。如何使用 vscode 終端:通過快捷鍵 (Ctrl/Cmd ) 打開終端。輸入命令或運行腳本。使用熱鍵 (如 Ctrl L 清除終端)。更改工作目錄 (如 cd 命令)。高級功能包括調試模式、代碼片段自動補全和交互式命令歷史。

要查看 Git 倉庫地址,請執行以下步驟:1. 打開命令行並導航到倉庫目錄;2. 運行 "git remote -v" 命令;3. 查看輸出中的倉庫名稱及其相應的地址。

在 Visual Studio Code(VSCode)中編寫代碼簡單易行,只需安裝 VSCode、創建項目、選擇語言、創建文件、編寫代碼、保存並運行即可。 VSCode 的優點包括跨平台、免費開源、強大功能、擴展豐富,以及輕量快速。

雖然 Notepad 無法直接運行 Java 代碼,但可以通過借助其他工具實現:使用命令行編譯器 (javac) 編譯代碼,生成字節碼文件 (filename.class)。使用 Java 解釋器 (java) 解釋字節碼,執行代碼並輸出結果。

Linux的主要用途包括:1.服務器操作系統,2.嵌入式系統,3.桌面操作系統,4.開發和測試環境。 Linux在這些領域表現出色,提供了穩定性、安全性和高效的開發工具。

VS Code 一步/下一步快捷鍵的使用方法:一步(向後):Windows/Linux:Ctrl ←;macOS:Cmd ←下一步(向前):Windows/Linux:Ctrl →;macOS:Cmd →

VS Code 終端命令無法使用的原因及解決辦法:未安裝必要的工具(Windows:WSL;macOS:Xcode 命令行工具)路徑配置錯誤(添加可執行文件到 PATH 環境變量中)權限問題(以管理員身份運行 VS Code)防火牆或代理限制(檢查設置,解除限制)終端設置不正確(啟用使用外部終端)VS Code 安裝損壞(重新安裝或更新)終端配置不兼容(嘗試不同的終端類型或命令)特定環境變量缺失(設置必要的環境變量)
