lib/stream-stats-view

What the dashboard draws of lib/stream-stats.js's contract, kept free of any framework so the two cannot read the same session differently: the four status rows and what makes one a warning, the figures under the graphs, the host meters, the geometry of a graph, and the plain-text report a user pastes into an issue.

A row warns where the session fell short of what it asked for, never for a choice and never for a server with no GPU, which is an ordinary deployment: software encoding somebody selected, or on a host exposed no GPU, is neutral, and software encoding on a session that asked for hardware where there is a GPU is a warning and carries pixelflux's reason. A readback in front of a hardware encoder is read the same way: it warns where the display server offered the encoder a zero-copy path (zero_copy_available) and the capture took a copy anyway, and is neutral on a server that offers none, such as an Xvfb with neither DRI3 nor NvFBC. The client's side reads the same way: software decoding warns only where a hardware decoder was there to take the stream, since a client without one is as ordinary as a server without a GPU, and a path through a relay or over TCP is how the network connects this client, which marks nothing either way, while a direct UDP path is good. Every value opens with a capital, and names the system reports (nvidia, renderD128, a decoder's own) are kept as reported. Technical values (NVENC, Zero-copy, renderD128) are not translated; the words a dashboard does translate arrive in words, and a figure's label is the dashboard's to word by the figure's key, the English here being the report's and the fallback.

InterfacesCopy Anchor Link

StreamRowCopy Anchor Link

Defined in: lib/stream-stats-view.js:44

One status row.

PropertiesCopy Anchor Link

keyCopy Anchor Link

key: "encoder" | "capture" | "decoder" | "connection";

Defined in: lib/stream-stats-view.js:45

statusCopy Anchor Link

status: "good" | "warn" | "neutral";

Defined in: lib/stream-stats-view.js:46

valueCopy Anchor Link

value: string;

Defined in: lib/stream-stats-view.js:47

The headline.

detailCopy Anchor Link

detail: string;

Defined in: lib/stream-stats-view.js:48

The quieter second line, may be empty.

reasonCopy Anchor Link

reason: string;

Defined in: lib/stream-stats-view.js:49

Why the row warns, empty unless it does.

StreamWordsCopy Anchor Link

Defined in: lib/stream-stats-view.js:53

The translated words the rows use.

PropertiesCopy Anchor Link

hardwareCopy Anchor Link

hardware: string;

Defined in: lib/stream-stats-view.js:54

softwareCopy Anchor Link

software: string;

Defined in: lib/stream-stats-view.js:55

unknownCopy Anchor Link

unknown: string;

Defined in: lib/stream-stats-view.js:56

throttledCopy Anchor Link

throttled: string;

Defined in: lib/stream-stats-view.js:57

Said when the server holds frames back.

hardware_availableCopy Anchor Link

hardware_available: string;

Defined in: lib/stream-stats-view.js:58

Why a software decode fell short where the engine has an efficient decoder for the stream.

software_preferredCopy Anchor Link

software_preferred: string;

Defined in: lib/stream-stats-view.js:60

Why it fell short where this client left a hardware decoder after it failed.

StreamInfoCopy Anchor Link

Defined in: lib/stream-stats.js:46

The server's description of the stream.

PropertiesCopy Anchor Link

backendCopy Anchor Link

backend: string;

Defined in: lib/stream-stats.js:47

x11 or wayland.

captureCopy Anchor Link

capture: string;

Defined in: lib/stream-stats.js:48

The capture path: NvFBC, DRI3, XShm, dmabuf, or readback.

zero_copyCopy Anchor Link

zero_copy: boolean;

Defined in: lib/stream-stats.js:50

Whether frames reach the encoder without a copy.

zero_copy_availableCopy Anchor Link

zero_copy_available: boolean;

Defined in: lib/stream-stats.js:51

Whether the display server offered the encoder a zero-copy path at all, so that a copy fell short of one.

capture_reasonCopy Anchor Link

capture_reason: string;

Defined in: lib/stream-stats.js:53

Why not, empty where there is nothing to explain.

encoderCopy Anchor Link

encoder: string;

Defined in: lib/stream-stats.js:54

NVENC, VAAPI, or the software library.

hardwareCopy Anchor Link

hardware: boolean;

Defined in: lib/stream-stats.js:55

Whether the encoder runs on a GPU.

gpu_presentCopy Anchor Link

gpu_present: boolean;

Defined in: lib/stream-stats.js:56

Whether the server is exposed a GPU at all.

hardware_expectedCopy Anchor Link

hardware_expected: boolean;

Defined in: lib/stream-stats.js:57

Whether the session asked for that on a server that has one.

encoder_reasonCopy Anchor Link

encoder_reason: string;

Defined in: lib/stream-stats.js:59

Why it does not.

codecCopy Anchor Link

codec: string;

Defined in: lib/stream-stats.js:60

fullcolorCopy Anchor Link

fullcolor: boolean;

Defined in: lib/stream-stats.js:61

Whether the stream is 4:4:4.

bit_depth?Copy Anchor Link

bit_depth?: number;

Defined in: lib/stream-stats.js:62

Bits per sample of the stream, 8 or 10.

stripedCopy Anchor Link

striped: boolean;

Defined in: lib/stream-stats.js:63

gpuCopy Anchor Link

gpu: string;

Defined in: lib/stream-stats.js:64

The GPU a hardware session encodes on.

driverCopy Anchor Link

driver: string;

Defined in: lib/stream-stats.js:65

Its kernel driver.

encode_nodeCopy Anchor Link

encode_node: string;

Defined in: lib/stream-stats.js:66

Its render node.

renderer?Copy Anchor Link

renderer?: string;

Defined in: lib/stream-stats.js:67

Wayland only: gl or pixman.

render_node?Copy Anchor Link

render_node?: string;

Defined in: lib/stream-stats.js:68

render_gpu?Copy Anchor Link

render_gpu?: string;

Defined in: lib/stream-stats.js:69

renderer_reason?Copy Anchor Link

renderer_reason?: string;

Defined in: lib/stream-stats.js:70

StreamClientCopy Anchor Link

Defined in: lib/stream-stats.js:74

This page's description of the stream.

PropertiesCopy Anchor Link

transportCopy Anchor Link

transport: "websockets" | "webrtc";

Defined in: lib/stream-stats.js:75

decoderCopy Anchor Link

decoder: "hardware" | "software" | "unknown";

Defined in: lib/stream-stats.js:76

decoder_evidenceCopy Anchor Link

decoder_evidence: string;

Defined in: lib/stream-stats.js:77

What that verdict rests on.

hardware_expectedCopy Anchor Link

hardware_expected: boolean;

Defined in: lib/stream-stats.js:78

Whether a hardware decoder was there to take the stream, so a software verdict fell short of it.

decoder_reasonCopy Anchor Link

decoder_reason: string;

Defined in: lib/stream-stats.js:80

Why a software decode fell short, a word the dashboards translate: hardware_available (the engine has an efficient decoder for the stream) or software_preferred (this client left a hardware decoder after it failed); empty where it did not.

codecCopy Anchor Link

codec: string;

Defined in: lib/stream-stats.js:84

resolutionCopy Anchor Link

resolution: string;

Defined in: lib/stream-stats.js:85

1920x1080.

pathCopy Anchor Link

path: string;

Defined in: lib/stream-stats.js:86

WebRTC only: the candidate pair, as host udp.

sinkCopy Anchor Link

sink: string;

Defined in: lib/stream-stats.js:87

How decoded frames reach the screen: a track generator feeding a <video>, a canvas a worker composites on, or the page's own canvas. Which one an engine allows is probed, so this is the one that was taken rather than the one preferred.

decode_pathCopy Anchor Link

decode_path: string;

Defined in: lib/stream-stats.js:91

JPEG only: what turns a stripe into a picture, and where it runs.

connectionCopy Anchor Link

connection: "ok" | "poor";

Defined in: lib/stream-stats.js:93

The server's verdict on this page's connection: poor while too many of its display's frames are lost on the way or held back for its link (ConnectionVerdict on the server). The server says so only when it changes, so it is kept with the stats shut.

Type AliasesCopy Anchor Link

StreamSampleCopy Anchor Link

type StreamSample = Object<string, number | boolean | string>;

Defined in: lib/stream-stats.js:100

One second's figures: the server's (cpu_percent, mem_used, mem_total, gpu_percent, gpu_mem_used, gpu_mem_total, encoded_fps, encode_ms, pipeline_ms, rtt_ms, throttled) where it sent them, and server, whether it did, this page's (fps, the frames the screen was handed, where the sink says so; present_ms, how long a frame took from its arrival to that; frames_not_shown since the opening, those decoded but never shown; mbps, received_mb since the opening, and whatever else its core measures, lib/present-meter.js for the three), and t, the time in ms.

Type ParametersCopy Anchor Link

VariablesCopy Anchor Link

OVERSHOOTCopy Anchor Link

const OVERSHOOT: 1.1 = 1.1;

Defined in: lib/stream-stats-view.js:202

How far above its CBR target a stream may run, the policy's bound, before its rate warns.

HOLD_MSCopy Anchor Link

const HOLD_MS: 5000 = 5000;

Defined in: lib/stream-stats-view.js:209

How long a time measured in an earlier second stands in for seconds that measured none, in ms: a still screen encodes nothing, so motion that comes and goes would otherwise blink its times out between frames.

GRAPH_POINTSCopy Anchor Link

const GRAPH_POINTS: 120 = 120;

Defined in: lib/stream-stats-view.js:327

Points a graph draws at most; a longer history is bucketed down to it by maximum.

FunctionsCopy Anchor Link

codecName()Copy Anchor Link

function codecName(codec): string;

Defined in: lib/stream-stats-view.js:67

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

string

nodeName()Copy Anchor Link

function nodeName(path): string;

Defined in: lib/stream-stats-view.js:69

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

string

joined()Copy Anchor Link

function joined(parts): string;

Defined in: lib/stream-stats-view.js:71

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

string

sentence()Copy Anchor Link

function sentence(text): string;

Defined in: lib/stream-stats-view.js:73

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

string

encoderRow()Copy Anchor Link

function encoderRow(info): StreamRow;

Defined in: lib/stream-stats-view.js:79

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

StreamRow

captureRow()Copy Anchor Link

function captureRow(info): StreamRow;

Defined in: lib/stream-stats-view.js:99

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

StreamRow

decoderRow()Copy Anchor Link

function decoderRow(client, words): StreamRow;

Defined in: lib/stream-stats-view.js:121

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

StreamRow

connectionRow()Copy Anchor Link

function connectionRow(
   client, 
   latest, 
   words
): StreamRow;

Defined in: lib/stream-stats-view.js:142

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

StreamRow

streamRows()Copy Anchor Link

function streamRows(
   info, 
   client, 
   latest, 
   words
): StreamRow[];

Defined in: lib/stream-stats-view.js:164

The four status rows, in display order.

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

StreamRow[]

figure()Copy Anchor Link

function figure(
   latest, 
   key, 
   history?
): object;

Defined in: lib/stream-stats-view.js:223

What a figure reads: its value with the unit, and for a time the server measured its range, as least–most, and whether it warns: the video rate when it runs past OVERSHOOT of its CBR target, which it is shown against. A time with nothing measured this second reads the last one measured within HOLD_MS (history), else idle where the stream moved no frame, else a dash.

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

object

valueCopy Anchor Link

value: string;

detailCopy Anchor Link

detail: string;

warnCopy Anchor Link

warn: boolean;

streamTiles()Copy Anchor Link

function streamTiles(
   latest, 
   transport, 
   history?
): object[];

Defined in: lib/stream-stats-view.js:265

The figures under the graphs: one fixed set per transport, so the layout holds still. A time is the last second's, its range under it where the server measured one, and the video rate the last ten seconds' against the CBR target with its fullest quarter second beside it; everything else counts from the opening: the data received, the packet loss, and each drop and repair. A figure with nothing measured this second keeps its place: a time reads its last measurement for a while (figure), and the rest a dash.

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

object[]

streamStrip()Copy Anchor Link

function streamStrip(latest, transport): object[];

Defined in: lib/stream-stats-view.js:279

The strip a dashboard lays over the stream: how fast frames reach the screen, the video rate against its target, and how long a frame takes from its capture to the wire, with the round trip over WebSockets, where the server measures one. Each names the tile, or graph, whose label captions it.

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

object[]

gib()Copy Anchor Link

function gib(bytes): string;

Defined in: lib/stream-stats-view.js:290

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

string

streamMeters()Copy Anchor Link

function streamMeters(latest): object[];

Defined in: lib/stream-stats-view.js:302

The host meters: the utilizations first and the memories under them, so the bars read as one block rather than alternating with the figures. A utilization carries a bar, which is what a share of a whole reads well as; a memory pair carries its amounts as the figure and no bar, because how much of how much is what an operator needs and a bar leaves it to a hover no touch screen has. The GPU rows are left out where the server reads no GPU.

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

object[]

seriesOf()Copy Anchor Link

function seriesOf(history, key): number[];

Defined in: lib/stream-stats-view.js:337

One series of a history, bucketed down to GRAPH_POINTS so a graph that has grown for ten minutes costs what a short one does. A bucket keeps its maximum, since a graph of a rate is read for its peaks.

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

number[]

graphPath()Copy Anchor Link

function graphPath(
   values, 
   width, 
   height, 
   max
): object;

Defined in: lib/stream-stats-view.js:355

A graph's SVG geometry. The history grows from the left edge until it fills the width, the way it reads while the stats stay open.

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

object

Path data for the stroke and the fill under it, and each point's coordinates.

lineCopy Anchor Link

line: string;

areaCopy Anchor Link

area: string;

xsCopy Anchor Link

xs: number[];

ysCopy Anchor Link

ys: number[];

streamReport()Copy Anchor Link

function streamReport(
   info, 
   client, 
   latest
): string;

Defined in: lib/stream-stats-view.js:372

The session as plain text, for an issue or a chat.

ParametersCopy Anchor Link

ReturnsCopy Anchor Link

string