remove wasm telemetry (#15315)

* remove wasm telemetry

* update link

* update link

content/en/blog/2020/wasm-announce/index.md

@@ -18,7 +18,7 @@ extensibility to the Envoy proxy using [WebAssembly](https://webassembly.org/).
 share that work with the world today, as well as
 unveiling [WebAssembly (Wasm) for Proxies](https://github.com/proxy-wasm/spec) (Proxy-Wasm): an ABI,
 which we intend to standardize; SDKs; and its first major implementation, the new,
-lower-latency [Istio telemetry system](/docs/reference/config/proxy_extensions/wasm_telemetry/).
+lower-latency [Istio telemetry system](https://istio.io/v1.6/docs/reference/config/proxy_extensions/wasm_telemetry/).
 
 We have also worked closely with the community to ensure that there is a great developer experience
 for users to get started quickly. The Google team has been working closely with the team

content/en/docs/reference/config/proxy_extensions/wasm_telemetry/index.md

@@ -1,33 +0,0 @@
----
-title: Wasm-based Telemetry
-description: How to enable telemetry generation with the Wasm runtime.
-weight: 60
-owner: istio/wg-policies-and-telemetry-maintainers
-test: no
-aliases:
-    - /docs/reference/config/telemetry/telemetry_v2_with_wasm/
-status: Experimental
----
-
-{{< boilerplate experimental >}}
-
-By default, telemetry generation is enabled as compiled-in Istio proxy filters. The same filters are also compiled to WebAssembly (Wasm) modules and shipped with Istio proxy. To enable telemetry generation with the Wasm runtime, install Istio with the `preview` profile:
-
-{{< text bash >}}
-$ istioctl install --set profile=preview
-{{< /text >}}
-
-Alternatively, set the following two values to enable Wasm-based Telemetry with the `default` profile:
-
-{{< text bash >}}
-$ istioctl install --set values.telemetry.v2.metadataExchange.wasmEnabled=true --set values.telemetry.v2.prometheus.wasmEnabled=true
-{{< /text >}}
-
-{{< warning >}}
-There are several known limitations with Wasm-based telemetry generation:
-
-* Proxy CPU usage will spike during Wasm module loading time (i.e. when the aforementioned configuration is applied). Increasing proxy CPU resource limit will help to speed up loading.
-* Proxy baseline resource usage increases. Based on preliminary performance testing result, comparing to the default installation, running Wasm-based telemetry will cost 30%~50% more CPU and double the memory usage.
-
-The performance will be continuously improved in the following releases.
-{{</ warning>}}