SSP — Website Speed Monitor (Docs)

SSP Documentation

SSP Website Speed Monitor

Admin Screen

Top-level menu SSP Speed Monitor (performance icon) opens a single page with three tabs:

Dashboard

Live — current 1-minute server load (auto-refreshing).
Controls & Settings — enable throttle, set Ceiling, choose sources to throttle, toggle admin-bar live number.
Averages — overall average and max observed load.
Load Throttle — current status (ACTIVE/IDLE) with ceiling and current load.
Throttle Sources & Events — counts by source, top URLs, and a detailed events table.

Analytics

Every hour of today — per-hour averages for the current day.
Every day of the week — overall averages Mon–Sun.
Every week this month — week-of-month averages.
Every month this year — Jan–Dec averages.
All years — per-year rows, average, and max.

Sources

LIVE breakdown that sums to the current 1-minute load by allocating load proportionally to request counts.
Sources: WP-Cron, Heartbeat, AJAX (other), Admin, Frontend, Other.

Tip: Use “Reset analytics data” on Dashboard to clear minute + hourly logs (safe; throttle log & sources counters remain).

How It Works

Activation ensures/creates four tables and schedules a per-minute logger; it also writes an initial sample.
Per-minute logger records the 1-minute load average and upserts a row keyed by YYYYMMDDHHMM.
Per-hour aggregator recomputes hourly averages from minute rows for the current hour and upserts an hourly row.
Always-on source counting increments a per-minute counter for the request’s source class (cron, heartbeat, ajax_other, admin, frontend, other).
Throttle optionally suppresses WP-Cron spawns and/or disables Heartbeat when the load meets/exceeds your ceiling; events are logged.
AJAX auto-refresh updates Live, Averages, Throttle, Analytics tiles, Sources, and admin-bar number every ~10s.
Fallback seeds a minute sample once per minute on traffic even if WP-Cron is stuck.
Degraded mode (no sys_getloadavg()): the plugin logs 0.00 so analytics still populate.

Data Model (Tables)

Per-minute log

Table	`wp_ssp_load_log`
Keys	PK `id`, UNIQUE `minute_key` (BIGINT), index `ts`
Columns	`ts DATETIME`, `minute_key BIGINT` (YYYYMMDDHHMM), `load FLOAT`

Per-hour aggregates

Table	`wp_ssp_load_hourly`
Keys	PK `id`, UNIQUE `hour_key` (BIGINT), index `ts`
Columns	`ts DATETIME` (last update), `hour_key BIGINT` (YYYYMMDDHH), `avg_load FLOAT`, `sample_count INT`

Throttle events

Table	`wp_ssp_throttle_log`
Keys	PK `id`, indexes `ts`, `source`
Columns	`ts DATETIME`, `source VARCHAR(32)` (cron_spawn \| heartbeat_block \| other), `url TEXT`, `ip`, `ua`

Request sources (per-minute counters)

Table	`wp_ssp_request_sources`
Keys	PK `id`, UNIQUE `minute_key`, index `ts`
Columns	`ts DATETIME`, `minute_key BIGINT`, `cron`, `heartbeat`, `ajax_other`, `admin`, `frontend`, `other`

Note: Legacy installs automatically heal minute_key to BIGINT.

Logging & Aggregation

Per-minute logger

Runs via WP-Cron schedule every 60s.
Upserts ts, minute_key, load.
Fallback seeding guarantees at least one write per minute on traffic.

Per-hour aggregator

Recomputes the average from minute rows for current hour window.
Upserts avg_load and sample_count.
Analytics tiles read from hourly where possible, minute otherwise.

Scheduling

Cron schedule key: ssp_wsm_every_minute (interval 60s).
Hook: ssp_wsm_log_every_minute.
On deactivation the event is unscheduled.

Dashboard

Live shows the current 1-minute load and the last refresh time.
Controls & Settings:
- Enable Load Throttle — master toggle.
- Ceiling — threshold; when load ≥ ceiling the throttle engages.
- Sources to Throttle — WP-Cron and/or Heartbeat (AJAX).
- Show Admin Bar Load Number — toggles the live number in the top bar.
- Reset analytics data — truncates minute + hourly tables.
Averages — overall average & max observed, for quick health checks.
Throttle box — Enabled, Ceiling, Current load, and Status (ACTIVE/IDLE).
Throttle Sources & Events — counts by source, top URLs by frequency, and a detailed events table (header shows “URL”, no “(truncated)”).

Analytics

Every hour of today — bars scaled to the max hour; uses hourly table, falls back to minute.
Every day of the week — Mon–Sun overall averages.
Every week this month — week-of-month averages (1..5).
Every month this year — Jan..Dec averages with month labels.
All years — per-year rows with total rows, average, and max.

Sources (LIVE)

The Sources tab tracks request counts for the current minute and allocates the live 1-minute load proportionally so the components sum to the total.

Sources tracked

WP-Cron
Heartbeat
AJAX (other)
Admin
Frontend
Other

How allocation works

Within the current minute, let N be the total requests across sources.
Each source gets live_load × (source_count / N).
Bars are scaled to the largest allocated component for visual clarity.

Note: Source counters are written on every request (independent of the throttle) and upserted per minute.

Load Throttle

Behavior

When enabled and load ≥ ceiling:
- WP-Cron spawns (requests to wp-cron.php) are suppressed via HTTP filter, and a throttle event is logged.
- Heartbeat is disabled by deregistering the script; a once-per-minute event is logged while active.
Each event records time, source, and (when available) URL.

Why throttle?

To reduce non-essential background load spikes during heavy traffic.
To keep the site responsive by delaying cron and editor heartbeat until load falls.

Caution: Throttling cron may delay scheduled tasks; choose a ceiling that balances responsiveness with task timeliness.

Admin Bar

Shows the live 1-minute load as a number.
Color shifts to red when the value is ≥ 1.00; otherwise green.
Toggle visibility in Controls & Settings.

AJAX & Auto-refresh

Every ~10 seconds an authenticated AJAX request returns updated HTML for:
- Live, Averages, Throttle box, Throttle events
- Per-hour today, Weekday, Week-of-month, Monthly, Years
- Sources (LIVE)
The response also includes the numeric live value to repaint the admin-bar node.
No-cache headers and a nonce are used; visibility-change triggers a refresh when you return to the tab.

Reset & Degraded Mode

Reset analytics

Dashboard → Reset analytics data truncates per-minute and per-hour tables.
Does not clear throttle events or source counters.

Degraded mode

If sys_getloadavg() is unavailable, the plugin logs 0.00 as load.
All tiles and charts still function so you can verify the pipeline.

Troubleshooting

No data appears

Confirm WP-Cron runs (traffic or a system cron hitting wp-cron.php).
Use the fallback seeding by simply visiting the Dashboard; it writes once per minute via transient.
Check DB user permissions for creating/altering tables.

Live number is always 0.00

Your environment may lack sys_getloadavg(); this is expected in some hosts/containers.
Analytics will still populate; consider enabling host-level metrics for real load values.

Throttle never engages

Enable Throttle and set the Ceiling below your current load for testing.
Ensure the specific source (WP-Cron or Heartbeat) is checked to be throttled.

Throttle blocks too aggressively

Raise the ceiling, or uncheck the source you don’t want to block.
Remember WP-Cron suppression can delay scheduled tasks.

Admin-bar number missing

Enable “Show Admin Bar Load Number” on Dashboard.
Verify you’re logged-in and the admin bar is visible.

Test / Verification

Visit Dashboard and confirm a Live value appears (may be 0.00 in degraded mode).
Click Reset analytics data, then wait ~1–2 minutes; verify per-hour today begins to fill.
Enable Load Throttle, set Ceiling to 0.00 temporarily, and tick both sources. Confirm:
- Status shows ACTIVE.
- Throttle Sources & Events table starts logging events.
- “Top URLs” lists wp-cron.php when cron spawns are suppressed.
Open the Sources tab and trigger various requests (navigate front-end, admin, run AJAX). Observe counts and allocated load change, summing to the live number.
Restore a sane ceiling (e.g., 25.00) and disable throttle if desired.

Tip: If your site has very low traffic, set up a system cron to hit wp-cron.php every minute to guarantee samples.