download eta always wrong

[blackmancer]

whenever I download a game or update, Steam will always give me a wrong guess as to how long it will take. It seems to usually halve the time e.g. if I know my connection can only download at a max 540MB/hr then how can 2000MB only take 1hr 35mins, which is what Steam tells me. It always gets it wrong and even Microsoft has a better record on file transfer estimations, and those guys suck at making software!

[ManiacMal]

It's always going to be wrong that's why it is called an eta. When you first start a download it is going by your connection speed at that point and marking a time, during the download your connection is going to fluctuate to different speeds depending on what else you are doing on your PC, if you are streaming youtube videos it's going to slow down. You can never expect any software to be able to accurately supply you with the correct eta right off the bat. Connections are not stable and you also relie on the steam servers to not bog down from traffic.

[blackmancer]

maybe I didn't explain, but it is suggesting a time that is impossible for the connection to provide. Steam provide an eta of half, meaning it thinks the connection is downloading at twice the capability of the connection.

also, explain why it can sit on a steady number like 150-160K/s but estimate incorrectly and think I'm downloading at 300K/s, even if the connection varies 10K that is a variance of less than 10%, not enough to cause a incorrect value like the one given

[ManiacMal]

I see what you are saying now and honestly I have no answer to that. The only thing I can think of is in your steam settings, in the downloads + cloud tab do you have your connection set to the correct connection rate? Ie. DSL if that is what you got, because if it's set to broadband then maybe that's why it might be inaccurate. Just a suggestion not a concreate answer.

[Felix]

It might also have something to do with you downloading compressed files?

Steam has an odd way of showing download speeds and download rates. If the file you are downloading is compressed Steam will show a download rate as equivilent to the uncompressed file.

As an example, you're downloading a 100MB file but it's compressed to a 50MB download. You are downloading a 1MB a second. Because the file is actually 100MB uncompressed, double what the compressed version is, Steam will show your double rate as double for that time, meaning it'll state the download rate as 2MB rather than 1MB a second.

If that makes sense?

[blackmancer]

the compressed files is really the only answer. I guess good job to valve for much compression but it would be nice if it was a little more accurate.