Odd fetching of radio

Jim web web at audiomisc.co.uk
Fri Feb 19 01:44:36 PST 2016

In article <2C200530D85044F3971052FA3FD01818 at vasonote>, Vangelis
<northmedia1 at the.forthnet.gr> wrote:
> On Thu Feb 18 12:04:59 GMT 2016, Jim web wrote:
[snip version deductions/info]

> On Thu Feb 18 11:33:04 GMT 2016, Jim web wrote:

> > I did a comparision this morning between using hls for TV fetching and
> > DASH for radio.

>  With respect, this is a classic case of apples and oranges. Some facts:

> [Do not compare GiP 2.94 and 2.95dev. The former uses FFmpeg for HLS,
> the latter uses by default for both HLS & DASH a native pure perl
> downloader (can switch to FFmpeg for HLS only, as FFmpeg does not do
> DASH).]

I'm afraid you may have missed the actual point of the comparision I was
reporting. Sorry if my explanations weren't clear.

The key point was that I did comparisions *before 9am* to see if that
cleared up the puzzlingly slooow fetchings via DASH. *Which had only been
occurring in recent days*. I wanted to see if the fetching was fast at that

This was to see if I found evidence to support concluding that for some
reason DASH radio fetching was being particularly slowed by the intensity
or nature of other net traffic *during the day*. *Not* to compare DASH wth

Underlaying that was the point that DASH radio fetching *had* been far
faster in the past than recently, at almost all times of day. So I was
testing what happened *at that time of day* to see if the DASH radio
fetching was fast at that time in the morning.

*If* I found a reliable pattern where dash fetching of radio was fast
before 9am but slow during the rest of the day I could have concluded the
recent problems were down to 'traffic' and nothing to do with using dash
per se. (TV fetching is very slow most of the day.) But the results I got
that morning were slow.

My next tests were to see if dashhigh / dashhigh1 / dashhigh2 made any
difference. But so far as I could tell, the variations were random and had
nothing to do with the choice.

This morning before 9am, though, I got the 'old' behaviour. I used dashhigh
and got a half-hour 320k file in less than one minute. I don't yet know if
that was simply luck or things have improved.

The puzzle here is that - until a couple of weeks ago - dashhigh radio
always ran quickly and I could get something like an hour long 320k
programme in about a minute or less. However more recently it has been
taking a *lot* longer, and often failed. What I still don't know, is why.
It is as if some kind of net activity is crowding it out for me.

FWIW I have for years experienced the behaviour where net speeds are much
slower during the day and evening than in the early morning. This applies
to essentially all 'real' activites, despite a claimed speed when I do the
BT test of about 70 megs. One reason I use get-iplayer is that trying to
watch the HDTV via the standard BBC interface is impossible during the day
or evenings. The fetching rate can't quite keep up. But before 9am I can
often get fetch rates around 350 frames/sec. This morning I got 450
frames/sec at about 7:30am. In the evenings even a reliable 25 frames/sec
would be difficult to obtain!


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