Re: downloading a single file using multiple threads

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On Wed, 28 Mar 2007 14:13:32 -0700, Willy Denoyette [MVP] <willy.denoyette@xxxxxxxxxx> wrote:

[...]
Not at all - and I don't recall picking on you particularly in the past
either :)

Yes, you did, I prefer not to go public on this.

For what it's worth, I didn't get the impression that anyone was picking on anyone else.

When such an impression is received by someone, it's also been my experience that it is almost always actually a case of one person simply trying to make sure they have the facts straight (and in the process drilling down into more detail than someone else thinks is necessary or warranted), or a case of two people who think they are talking about the same thing turning out to not be talking about the same thing, or both.

Honestly, I have seen precious little of what I'd call "picking on" in this newsgroup. It's one of the reasons it's one of the few newsgroups I still bother to read.

That said...

You repeatedly say (correctly, as far as I'm aware) that it can't be
done on a single connection (with HTTP/FTP) but that's a straw man that
no-one's actually suggested - so why keep talking about it?


I guess that Peter suggested this (excuse Peter if I got this wrong) by saying

See, for example, the "Range" field in HTTP.

http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.35.1

You are excused. :)

If you'll look, you'll note that I posted that simply in reply to your statement about whether it was possible to request a file fragment via HTTP or FTP. The context had nothing to do (at the time) with numbers of connections, sessions, etc. It was just a question of whether those protocols had any way to specify some subset during a download.

In particular, here is the statement to which I replied (and quoted in my post):

"How do you indicate what chunk of the file you want when say using FTP? As far as I know this is not part of the FTP neither of HTTP protocol"

Nothing in there about connections or sessions. Just the question of indicating what chunk of a file you want when using FTP or HTTP.

well, having multiple threads without the possibility to have overlapped range requests per connection makes no sense, having multiple threads requesting chunks over 2 connections (HTTP1.1) makes little sense IMO either, unless you have measured the real benefits.

Well, as has been adequately described already I think, there are definitely scenarios in which there is a measurable benefit.

<snip>

I don't even know whether the OP isn't simply talking about a file
server request using System.IO.

Indeed. It would be nice if the OP would return to the thread :)

That's the real problem these day's, they come up with a vague question they get some confusing answers (our mistakes?), finally they get side tracked (by us) and they never come back, they are scared off, really.

Well, hopefully the worthy ones recognize the ambiguity in their question and post a clarification. :)

But I'd agree that it's our fault when we answer a question before we really understand it. Hopefully we haven't done too much of that here. :)

Pete
.

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