使用 aria2c 下载单个大文件

Question

I want to download a file that is around 60GB in size.

My internet speed is 100mbps but download speed is not utilizing my entire bandwidth.

If I use aria2c to download this single file, I can utilize increased "connections per server"? It seems aria2c lets me use 16 max connections. Would this option even work for downloading a single file?

The way I'm visualizing how the download goes is like 1 connection tries to download from 1 sector of the file, while the other connection tries to download from a different sector. And basically, the optimal number of concurrent download is until the host bandwidth limit is reached (mine being 100mbps). And when the two connections collide in the sectors they are downloading, then aria2c would immediately see that that specific sector is already downloaded and skips to a different sector. Is this how it plays out when using multiple connections for a single file?

Answer 1

Is this how it plays out when using multiple connections for a single file?

HTTP standard provideRange request header, which allow to say for example: I want part of file, starting at byte X and ending at byte Y. If server do support this gimmick then it respond with 206 Partial Content . Thus knowing length (size) of file (see Content-Length ) it is possible to lay parts so they are disjoint and cover whole file.

Beware that not all servers support this gimmick. You need to check if server hosting file you want to download do so. This can be done using HEAD request, HTTP range requests provides example using curl

curl -I http://i.imgur.com/z4d4kWk.jpg

HTTP/1.1 200 OK
...
Accept-Ranges: bytes
Content-Length: 146515

If you have bytes in Accept-Ranges this mean that server does have support. If you wish you might any other tool able to send HEAD request and provide to you response headers.