Files
udpscope/help/C/org.udpscope.app/status.page
T

73 lines
4.0 KiB
Plaintext

<page xmlns="http://projectmallard.org/1.0/"
type="topic" style="task"
id="status">
<info>
<link type="guide" xref="index#output"/>
<desc>The status bar's two tiers, the activity badge, the fixed state words, and the ⓘ
detail popover.</desc>
<credit type="author copyright">
<name>Martino Ferrari</name>
</credit>
</info>
<title>Status bar and diagnostics</title>
<p>The status bar is two tiers. The bar itself is one glance line — the state, the rate and
the window — and everything else is behind the ⓘ button at its right-hand end.</p>
<section id="reach">
<title>How to reach it</title>
<p>The bar is always visible at the foot of the window, under the badge bar. Click <gui>ⓘ</gui> for the detail popover.</p>
</section>
<section id="knowing">
<title>Worth knowing</title>
<list>
<item><p>The badge is one glyph in four colours: green <em>alternating</em> lit and dim
means data is arriving, and a steady colour means it is not. A badge that never blinks is
not a working badge. Of the two steady colours, <em>grey</em> is no stream at all or a
pipeline you stopped (the tooltip says which), and <em>yellow</em> is a source that
answered but has sent no configuration.</p></item>
<item><p>The state field is one word from a fixed set: <code>connecting</code>,
<code>live</code>, <code>paused</code>, <code>armed</code>, <code>capturing</code>,
<code>event held</code>, <code>disarmed</code>. Two states add one field each: in trigger
mode, how long ago the last event was; while paused, how long you have been paused.</p></item>
<item><p><code>connecting</code> means there is no <em>signal list</em> yet — either no
session or a session with no configuration behind it. Every other word claims a signal
list, so until one arrives there is nothing for them to describe: nothing can be enabled
and no data is owed.</p></item>
<item><p>The paused figure is <em>wall</em> time, not stream time — the producer never
stops while paused, so it answers "how long have I been looking at this picture".</p></item>
<item><p>Nothing on the bar may change width with the stream, because the bar sits
directly above the plot and a wider label would relayout it. That is why the rate
collapses to one figure or a range rather than listing per channel, and why an elapsed
time steps to a coarser unit instead of growing digits.</p></item>
<item><p><code>gaps</code> counts packets the receiver knows it missed. It is the number
that matters: a non-zero count means samples are absent from the buffer, not merely
late.</p></item>
<item><p><code>reconnects</code> counts sessions re-established with the source. Over
unicast a climbing count usually means a second client is taking the source's single
session.</p></item>
<item><p>The starvation notice — <em>connected, but no data is arriving</em> — is that
same situation seen from the other side: the signal list is here, so something took the
stream away. A source that has sent <em>no</em> configuration gets a different notice,
<em>trying to connect</em>, because nothing was taken away — pointing the app at a port
where nothing answers is that case, and the usual cause is a streamer that is not running
or is serving another port.</p></item>
<item><p><code>stored</code> versus <code>wire</code> in the popover is the decimation.
They differ exactly when the window is too long to store at full rate.</p></item>
</list>
</section>
<section id="example">
<title>Example</title>
<p>The bar reads <code>● live · 10 kS/s · 2 s window</code>. Behind ⓘ:
<code>Stream connected, configured / packets 717 · frames 716 · gaps 0 / 3 signals · 3
channels</code>, <code>Buffer 200.0 MB · 1677 s span · time x1 / stored 10 kS/s (wire
10 kS/s)</code>, <code>Plot 1 3 traces · 195000 samples</code>,
<code>Reconnects 0</code>.</p>
</section>
</page>