Overview

fcopy - utility to copy files. Before copying the file fcopy finds its total size and requests OS to allocate free space for a new copy in advance. After space is allocated fcopy starts multiple worker threads which read data from the source file in blocks of certain size and write them to the destination file.

At that moment fcopy does not support data integrity verification after the files were copied. Please use md5sum/crcsum if needed. fcopy relies on Java IO and if it does not throw an exception then fcopy considers data as being written to the disk without any corruptions.

Download

You can download fcopy from here

Requirements

Java 11

Usage

fcopy [ OPTION ]... SRC DST

Where:

• SRC - source which may be either file or directory. In case of directory fcopy will copy all content of it recursively
• DST - destination which may be either file or directory depending from the SRC you use

Options:

-bs BLOCK_SIZE - when fcopy reads and writes data it does it in blocks of given size in bytes (default is 256K as the most popular among SSD drives)

-t NUMBER_OF_THREADS - number of worker threads which will copy the data in parallel (default is number of cores in the system)

-c QUEUE_CAPACITY - size of internal queue from which worker threads pick up the blocks they need to copy (default is NUMBER_OF_THREADS^2)

-s - enables silent mode

Examples

Copy ~/test file to /tmp directory:

Measurements

Below are the measurements between fcopy, rsync and cp.

Single file

Test files:

• ubuntu-18.04.1-desktop-amd64.iso 1.9G (1953349632)

fcopy

Default:

With 1MB block size:

With 30 threads and 2048000 block size:

rsync

cp

Multiple files

Test folder:

• lubuntu-18.04-alternate-amd64.iso 717M (751828992)
• lubuntu-19.04-desktop-amd64.iso 1.6G (1657700352)
• ubuntu-18.04.1-desktop-amd64.iso 1.9G (1953349632)
• ubuntu-18.04.1-server-amd64.iso 715M (749731840)
• ubuntu-19.10-server-amd64.iso 785M (823132160)

fcopy

Default;

With 2048000 block size:

With 4096000 block size:

rsync

cp