From f2648b263b69aecca529c14fd5441503850a7c0d Mon Sep 17 00:00:00 2001
From: Wolfgang Walther <walther@technowledgy.de>
Date: Wed, 6 Aug 2025 14:40:30 +0200
Subject: [PATCH] workflows/eval: disable swap

Recent performance tests show that (a) swapping heavily slows down the
Eval job, while (b) lowering the chunkSize does not have an effect on
run-time. It does on memory usage, though - thus we can get rid of
swapping entirely by reducing chunkSize respectively.
---
 .github/workflows/eval.yml | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/.github/workflows/eval.yml b/.github/workflows/eval.yml
index 5999aedcb9382..805f8572cf152 100644
--- a/.github/workflows/eval.yml
+++ b/.github/workflows/eval.yml
@@ -32,12 +32,11 @@ jobs:
     outputs:
       targetRunId: ${{ steps.targetRunId.outputs.targetRunId }}
     steps:
-      - name: Enable swap
+      # We'd rather fail than run slow eval on swap.
+      # Failing allows us to adjust the chunkSize to remain fast.
+      - name: Disable swap
         run: |
-          sudo fallocate -l 10G /swap
-          sudo chmod 600 /swap
-          sudo mkswap /swap
-          sudo swapon /swap
+          sudo swapoff -a
 
       - name: Check out the PR at the test merge commit
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
@@ -56,7 +55,7 @@ jobs:
         run: |
           nix-build untrusted/ci -A eval.singleSystem \
             --argstr evalSystem "$MATRIX_SYSTEM" \
-            --arg chunkSize 10000 \
+            --arg chunkSize 8000 \
             --out-link merged
           # If it uses too much memory, slightly decrease chunkSize