Update weight-generation.md

docs/weight-generation.md

@@ -2,100 +2,40 @@
 
 To generate weights for a runtime
 
-1. Build `chain-spec-generator` with `--profile production --features runtime-benchmarks`
-2. Use it to build a chain spec for your runtime, e.g. `./target/production/chain-spec-generator --raw polkadot-local > polkadot-chain-spec.json`
-3. Create `file_header.txt`
+In a PR run the actions through comment:
 
-```text
-// Copyright (C) Parity Technologies and the various Polkadot contributors, see Contributions.md
-// for a list of specific contributors.
-// SPDX-License-Identifier: Apache-2.0
+```sh
+/cmd bench --help # outputs the actual usage documentation with examples and supported runtimes
 
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-```
-
-4. `rsync` chain spec/s and the file header to a benchmark machine
-
-5. Build `polkadot` binary from the latest release of `polkadot-sdk` with `--profile production --features runtime-benchmarks --bin polkadot` on the benchmark machine
-
-6. Run on the benchmark machine:
-
-```bash
-#!/bin/bash
-
-# Default value is 'polkadot', but you can override it by passing a different value as an argument
-CHAIN=${1:-polkadot}
-
-pallets=($(
-  ./target/production/polkadot benchmark pallet --list \
-    --chain=./$CHAIN-chain-spec.json |
-    tail -n+2 |
-    cut -d',' -f1 |
-    sort |
-    uniq
-));
+# or
 
-mkdir -p ./$CHAIN-weights
-for pallet in "${pallets[@]}"; do
-  output_file=./$CHAIN-weights/
-  # a little hack for pallet_xcm_benchmarks - we want to output them to a nested directory
-  if [[ "$pallet" == "pallet_xcm_benchmarks::generic" ]] || [[ "$pallet" == "pallet_xcm_benchmarks::fungible" ]]; then
-    mkdir -p ./$CHAIN-weights/xcm
-    output_file="${output_file}xcm/${pallet//::/_}.rs"
-  fi
-  echo "Running benchmarks for $pallet to $output_file"
-  ./target/production/polkadot benchmark pallet \
-    --chain=./$CHAIN-chain-spec.json \
-    --steps=50 \
-    --repeat=20 \
-    --pallet=$pallet \
-    --extrinsic=* \
-    --wasm-execution=compiled \
-    --heap-pages=4096 \
-    --output="$output_file" \
-    --header=./file_header.txt
-done
+/cmd --help # to see all available commands
 ```
 
-You probably want to do this inside a `tmux` session or something similar (e.g., `nohup <bench-cmd> &`), as it will take a while (several hours).
-
-7. `rsync` the weights back to your local machine, replacing the existing weights.
-
-8. Manually fix XCM weights by
-- Replacing `impl<T: frame_system::Config> xxx::yyy::WeightInfo<T> for WeightInfo<T> {` with `impl<T: frame_system::Config> WeightInfo<T> {`
-- Marking all functions `pub(crate)`
-- Removing any unused functions
-
-9. Commit the weight changes.
+To generate weights for all pallets in a particular runtime(s), run the following command:
+```sh
+/cmd bench --runtime kusama polkadot
+```
 
-10. Ensure the changes are reasonable. If not installed, `cargo install subweight`, check the weight changes:
-   ```
-   subweight compare commits \
-      --path-pattern "./**/weights/**/*.rs" \
-      --method asymptotic \
-      --ignore-errors \
-      <LATEST-RELEASE-BRANCH> \
-      <ACTUAL_BRANCH_WITH_COMMITED_WEIGHTS>`
-   ```
-   _Hint1: Add `--format markdown --no-color` for markdown-compatible results._
+> **📝 Note**: The action is not being run right-away, it will be queued and run in the next available runner. So might be quick, but might also take up to 10 mins (That's in control of Github).  
+Once the action is run, you'll see reaction 👀 on original comment, and if you didn't pass `--quiet` - it will also send a link to a pipeline when started, and link to whole workflow when finished.
 
-   _Hint2: Change `--path-pattern "./**/weights/**/*.rs"` to e.g. `--path-pattern "./relay/polkadot/weights/**/*.rs"` for a specific runtime._
+> **💡Hint #1** : if you run all runtimes or all pallets, it might be that some pallet in the middle is failed to generate weights, thus it stops (fails) the whole pipeline. 
+> If you want, you can make it to continue running, even if some pallets are failed, add `--continue-on-fail` flag to the command. The report will include which runtimes/pallets have failed, then you can re-run them separately after all is done. 
 
-   _Hint3: Add `--change added changed` to include only relevant changes._
+This way it runs all possible runtimes for the specified pallets, if it finds them in the runtime
+```sh 
+/cmd bench --pallet pallet_balances pallet_xcm_benchmarks::generic pallet_xcm_benchmarks::fungible
+```
 
-## FAQ
+If you want to run all specific pallet(s) for specific runtime(s), you can do it like this:
+```sh
+/cmd bench --runtime bridge-hub-polkadot --pallet pallet_xcm_benchmarks::generic pallet_xcm_benchmarks::fungible
+```
 
-### What benchmark machine spec should I use?
 
-See the [Polkadot Wiki Reference Hardware](https://wiki.polkadot.network/docs/maintain-guides-how-to-validate-polkadot#standard-hardware).
+> **💡Hint #2** : Sometimes when you run too many commands, or they keep failing and you're rerunning them again, it's handy to add `--clean` flag to the command. This will clean up all yours and bot's comments in PR relevant to /cmd commands.
 
+```sh
+/cmd bench --runtime kusama polkadot --pallet=pallet_balances --clean --continue-on-fail
+```