The thing about download managers…

Here’s something I keep seeing in the webserver’s log (IP address anonymized) all the time:

And this is actually a rather tame example with “only” 17 requests (can be considerably more). What’s happening there? Well, The user in question is retrieving my apk downloader with a download manager. The annoying thing about these applications is that they are often advertised with a feature called “download acceleration” and that what causes the problem above.

Some websites try to artificially limit download speed  (usually to make you pay for getting things faster) by limiting the bandwidth per connection. Download managers try to circumvent that cap by simply opening multiple connections and each of them only retrieves a (small) segment of the file.

Sounds smart? Isn’t! You are actually shooting yourself in the foot with this. My webserver doesn’t cap bandwidth. I have no interest in stalling file transfers. It actually costs me if you take longer and here’s why: each connection has overhead (the smaller your segments, the bigger the overhead!) this alone results in things going slower, not faster! However, the far greater issue is that my webserver will only serve a limited number of requests at the same time. Requests beyond that limit will get queued (or worse: dropped).

In other words: please don’t use download managers with a “download acceleration” feature. On most websites you will just end up stalling yourself and others as well.