diff --git a/docker/test/performance-comparison/compare.sh b/docker/test/performance-comparison/compare.sh
index 533a5963423..eba6aba0637 100755
--- a/docker/test/performance-comparison/compare.sh
+++ b/docker/test/performance-comparison/compare.sh
@@ -189,6 +189,10 @@ function run_tests
         grep ^client-time "$test_name-raw.tsv" | cut -f2- > "$test_name-client-time.tsv"
         # this may be slow, run it in background
         right/clickhouse local --file "$test_name-queries.tsv" --structure 'query text, run int, version UInt32, time float' --query "$(cat $script_dir/eqmed.sql)" > "$test_name-report.tsv" &
+
+        # Check that both servers are alive, to fail faster if they die.
+        left/clickhouse client --port 9001 --query "select 1 format Null"
+        right/clickhouse client --port 9002 --query "select 1 format Null"
     done
 
     unset TIMEFORMAT
diff --git a/docker/test/performance-comparison/entrypoint.sh b/docker/test/performance-comparison/entrypoint.sh
index 31ca70f91ef..bb5c2f6dbee 100755
--- a/docker/test/performance-comparison/entrypoint.sh
+++ b/docker/test/performance-comparison/entrypoint.sh
@@ -57,5 +57,7 @@ set -m
 time ../compare.sh 0 $ref_sha $PR_TO_TEST $SHA_TO_TEST 2>&1 | ts "$(printf '%%Y-%%m-%%d %%H:%%M:%%S\t')" | tee compare.log
 set +m
 
+dmesg > dmesg.log
+
 7z a /output/output.7z *.log *.tsv *.html *.txt *.rep
 cp compare.log /output