From 2db5fa0ca22b967e0b9f359275278c95f690b4eb Mon Sep 17 00:00:00 2001
From: David Hewitt <1939362+davidhewitt@users.noreply.github.com>
Date: Tue, 20 Jun 2023 17:15:08 +0100
Subject: [PATCH] try pgo for benchmarks run

---
 .github/workflows/codspeed.yml | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/codspeed.yml b/.github/workflows/codspeed.yml
index 97cf2c15e..dde22effd 100644
--- a/.github/workflows/codspeed.yml
+++ b/.github/workflows/codspeed.yml
@@ -41,12 +41,31 @@ jobs:
         if: steps.cache-py.outputs.cache-hit != 'true'
 
       - name: install rust stable
+        id: rust-toolchain
         uses: dtolnay/rust-toolchain@stable
+        with:
+          components: llvm-tools
 
       - name: cache rust
         uses: Swatinem/rust-cache@v2
 
-      - name: Install pydantic-core
+      - name: Compile pydantic-core for profiling
+        # build-prod does not include MiMalloc because it bypasses Maturin
+        run: |
+          pip install -e .
+          make build-prod
+          python -c 'import pydantic_core'
+        env:
+          CONST_RANDOM_SEED: 0 # Fix the compile time RNG seed
+          RUSTFLAGS: "-Cprofile-generate=${{ github.workspace }}/profdata"
+
+      - name: Gather pgo data
+        run: pytest
+
+      - name: Prepare merged pgo data
+        run: ~/.rustup/toolchains/${{ steps.rust-toolchain.outputs.name }}/lib/rustlib/x86_64-unknown-linux-gnu/bin/llvm-profdata merge -o ${{ github.workspace }}/merged.profdata ${{ github.workspace }}/profdata
+
+      - name: Compile pydantic-core for benchmarking
         # build-prod does not include MiMalloc because it bypasses Maturin
         run: |
           pip install -e .
@@ -54,6 +73,7 @@ jobs:
           python -c 'import pydantic_core'
         env:
           CONST_RANDOM_SEED: 0 # Fix the compile time RNG seed
+          RUSTFLAGS: "-Cprofile-use=${{ github.workspace }}/merged.profdata"
 
       # this is required so that pytest uses the installed package
       - run: rm tests/__init__.py