updated readme

Author: milindsrivastava1997

asap-dropin/README.md

@@ -13,17 +13,12 @@ On startup, all queries are forwarded transparently to your upstream Prometheus.
 ## Architecture
 
 ```
-Your Prometheus ──remote_write──▸ ASAPQuery (:9091/receive)
-                                      │
-                                      ▼
-Your Grafana ◂──query──── ASAPQuery Query Engine (:8088)
-                                      │
-                                      ▼ (fallback / passthrough)
-                               Your Prometheus
+Prometheus ──remote_write──▶ ASAPQuery (:9091)
+    ▲                              │
+    │ unsupported queries          ▼ builds sketches
+    └──────────── ASAPQuery (:8088) ◀── Grafana
 ```
 
-The query engine embeds the planner and runs it automatically after observing real Grafana queries for one observation window. No separate planner container, no Kafka, no Arroyo.
-
 ## Setup
 
 ### Step 1 — Configure environment
@@ -34,13 +29,12 @@ Edit `.env` to match your deployment:
 |---|---|---|
 | `PROMETHEUS_URL` | `http://host.docker.internal:9090` | URL of your Prometheus, reachable from inside the ASAPQuery container |
 | `PROMETHEUS_SCRAPE_INTERVAL` | `15` | Your Prometheus scrape interval in seconds |
-| `REMOTE_WRITE_PORT` | `9091` | Host port for the remote-write receiver |
-| `QUERY_ENGINE_PORT` | `8088` | Host port for the ASAPQuery query engine |
+| `REMOTE_WRITE_PORT` | `9091` | ASAPQuery data ingest port — must be free on the host |
+| `QUERY_ENGINE_PORT` | `8088` | ASAPQuery query endpoint port — must be free on the host |
 | `TRACKER_OBSERVATION_WINDOW_SECS` | `180` | How long to observe queries before planning (see note below) |
 
 **Finding the right `PROMETHEUS_URL`:**
-- **Docker Desktop (Mac/Windows):** `http://host.docker.internal:9090` (default)
-- **Linux (Prometheus on host):** `http://172.17.0.1:9090` (default Docker bridge gateway)
+- **Prometheus on the same host as Docker:** `http://172.17.0.1:9090` (default Docker bridge gateway on Linux)
 - **Prometheus in another Docker Compose:** use a shared external Docker network and the Prometheus service name
 
 **Setting `TRACKER_OBSERVATION_WINDOW_SECS`:**
@@ -58,7 +52,7 @@ docker compose up -d
 Verify it started:
 
 ```bash
-docker compose logs -f queryengine
+docker compose logs queryengine
 ```
 
 You should see a line confirming Prometheus is reachable, then the engine waiting for the observation window.
@@ -77,7 +71,7 @@ remote_write:
       sample_age_limit: 5m
 ```
 
-> **Finding the right `remote_write` URL:** The URL is from Prometheus's perspective, not your browser's.
+> **Finding the right `remote_write` URL:** The URL is from Prometheus's perspective.
 > - **Prometheus on the same host as Docker:** `http://localhost:9091/receive` (default above)
 > - **Prometheus in Docker on the same host:** `http://host.docker.internal:9091/receive` (Mac/Windows) or `http://172.17.0.1:9091/receive` (Linux)
 > - Change `9091` if you set a different `REMOTE_WRITE_PORT` in `.env`
@@ -89,39 +83,34 @@ If Prometheus was started with `--web.enable-lifecycle`:
 curl -X POST http://localhost:9090/-/reload
 ```
 
-Otherwise, restart your Prometheus process or container:
+Otherwise, send SIGHUP to the Prometheus process:
 ```bash
-# systemd
-sudo systemctl restart prometheus
-
-# Docker Compose
-docker compose restart prometheus
+kill -HUP $(pgrep prometheus)
 ```
 
-**Verify remote_write is active** by checking Prometheus logs for a line like:
-```
-level=info msg="Remote storage started"
-```
+See the [Prometheus configuration docs](https://prometheus.io/docs/prometheus/latest/configuration/configuration/) for more details on reloading.
 
-### Step 4 — Point Grafana at ASAPQuery
+### Step 4 — Add an ASAPQuery datasource in Grafana
 
-Grafana needs to send its queries to ASAPQuery instead of directly to Prometheus.
+Create a new datasource in Grafana pointing at ASAPQuery, then switch your dashboards to use it.
 
 1. Open Grafana in your browser
-2. Go to **Connections → Data Sources** (or **Configuration → Data Sources** in older Grafana)
-3. Click on your existing Prometheus datasource
-4. Change the **URL** field from your current Prometheus address to:
+2. Go to **Connections → Data Sources**
+3. Click **Add new data source** and select **Prometheus**
+4. Set the **Name** to something like `ASAPQuery`
+5. Set the **URL** to:
    ```
    http://localhost:8088
    ```
    (Change the port if you set a different `QUERY_ENGINE_PORT` in `.env`)
-5. Click **Save & Test** — you should see "Data source is working"
+6. Click **Save & Test** — you should see "Data source is working"
+7. Open your dashboards and switch their datasource to `ASAPQuery`
 
-ASAPQuery speaks the Prometheus HTTP API. Grafana does not need any other changes.
+ASAPQuery speaks the Prometheus query API. Queries it can accelerate are answered from sketches; all others are transparently forwarded to your upstream Prometheus, so your dashboards continue to work.
 
 ### Step 5 — Verify end-to-end
 
-Open your Grafana dashboards and use them normally. During the observation window, all queries pass through to Prometheus transparently — your dashboards continue to work.
+Use your Grafana dashboards normally. During the observation window, all queries pass through to Prometheus transparently.
 
 After the observation window elapses, check the ASAPQuery logs:
 
@@ -134,7 +123,7 @@ You should see lines like:
 query_tracker: planner succeeded — streaming aggregations: N, inference queries: M
 ```
 
-From this point on, queries that ASAPQuery can accelerate are served from sketches. Check the routing in the logs:
+From this point on, check the routing in the logs:
 
 ```bash
 docker compose logs queryengine | grep "destination="