[management] Keep per-table tablespaces in the MySQL test container

With innodb_file_per_table off, the packages that create hundreds of
databases per run got slower, not faster, while the small ones sped up:
dropped databases leave the shared system tablespace to grow and
fragment, so every later CREATE and DROP pays for it. Keep the default
per-table files and only skip the redo, binary log and doublewrite
fsyncs.

The temporary timing workflow also prints a short disk and CPU
calibration so a slow runner can be told apart from a slow change.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EsVtbd7MxMVsS9vP1H6KPS

.github/workflows/tmp-management-timing.yml

@@ -68,6 +68,14 @@ jobs:
           docker pull mlsmaycon/warmed-mysql:8
           docker image inspect mlsmaycon/warmed-mysql:8 --format 'entrypoint={{json .Config.Entrypoint}} cmd={{json .Config.Cmd}} env={{json .Config.Env}}'
 
+      - name: Runner calibration
+        run: |
+          nproc
+          grep -m1 "model name" /proc/cpuinfo
+          time dd if=/dev/zero of=/tmp/calib bs=1M count=256 conv=fsync
+          time sh -c 'for i in $(seq 1 200); do dd if=/dev/zero of=/tmp/calib-$i bs=4k count=1 conv=fsync 2>/dev/null; done'
+          rm -f /tmp/calib*
+
       - name: Build test summarizer
         run: go build -o /tmp/gotestsummary ./tools/gotestsummary
 

management/server/testutil/store.go

@@ -39,11 +39,12 @@ func CreateMysqlTestContainer() (func(), string, error) {
 		mysql.WithPassword("testing"),
 		// Every test creates and drops a database with about 40 tables, so with
 		// the server defaults the run is dominated by durability work: each
-		// CREATE TABLE creates and fsyncs its own tablespace file and fsyncs the
-		// redo and binary logs. None of it protects anything in a container that
-		// is discarded after the run.
+		// CREATE TABLE fsyncs the redo log, the binary log and the doublewrite
+		// buffer. None of it protects anything in a container that is discarded
+		// after the run. Tables stay in per-table files on purpose: in the shared
+		// system tablespace the cost of every CREATE and DROP grew with the number
+		// of databases the run had already created.
 		testcontainers.WithCmd("mysqld",
-			"--innodb-file-per-table=OFF",
 			"--innodb-flush-log-at-trx-commit=0",
 			"--innodb-doublewrite=OFF",
 			"--skip-log-bin",