diff --git a/.github/workflows/jtreg.yml b/.github/workflows/jtreg.yml
index fc7bacd..7ead5c1 100644
--- a/.github/workflows/jtreg.yml
+++ b/.github/workflows/jtreg.yml
@@ -62,6 +62,11 @@ jobs:
             ~/.cache/java-web/jdk-*
             ~/.cache/java-web/dejavu-*
           key: jdk-${{ runner.os }}-${{ runner.arch }}-${{ hashFiles('scripts/build-jdk.sh') }}
+      # TestNG and JUnit, which scripts/jtreg/run.ts fetches from Maven Central
+      - uses: actions/cache@v6
+        with:
+          path: build/jtreg/lib
+          key: jtreg-lib-${{ hashFiles('scripts/jtreg/run.ts') }}
       - run: pnpm install --frozen-lockfile
       - run: pnpm jdk
       # each test VM starts from the bundle, which loads faster than src/
diff --git a/scripts/jtreg/run.ts b/scripts/jtreg/run.ts
index 5aa1aa5..7d8dee1 100644
--- a/scripts/jtreg/run.ts
+++ b/scripts/jtreg/run.ts
@@ -227,7 +227,12 @@ async function fetchFrameworks(): Promise<string[]> {
   for (const [path, sha1] of frameworkJars) {
     const jar = join(lib, path.slice(path.lastIndexOf("/") + 1));
     if (!existsSync(jar)) {
-      const res = await fetch(maven + path);
+      // Maven Central answers 429 when many CI jobs start at once
+      let res = await fetch(maven + path);
+      for (let wait = 5; (res.status === 429 || res.status >= 500) && wait <= 80; wait *= 2) {
+        await new Promise((r) => setTimeout(r, wait * 1000));
+        res = await fetch(maven + path);
+      }
       if (!res.ok) throw new Error(`${res.status} fetching ${path}`);
       const bytes = Buffer.from(await res.arrayBuffer());
       const sum = createHash("sha1").update(bytes).digest("hex");
diff --git a/test/jtreg/passing.txt b/test/jtreg/passing.txt
index cdfb06c..d35c862 100644
--- a/test/jtreg/passing.txt
+++ b/test/jtreg/passing.txt
@@ -1426,7 +1426,6 @@ java/math/BigDecimal/ToPlainStringTests.java
 java/math/BigDecimal/ValueOfDouble.java
 java/math/BigDecimal/ZeroScalingTests.java
 java/math/BigInteger/BigIntegerParallelMultiplyTest.java
-java/math/BigInteger/BitLengthOverflow.java
 java/math/BigInteger/CompareToTests.java
 java/math/BigInteger/DoubleValueOverflow.java
 java/math/BigInteger/HashCode.java
diff --git a/test/jtreg/times.tsv b/test/jtreg/times.tsv
index 46d0c63..0d435c2 100644
--- a/test/jtreg/times.tsv
+++ b/test/jtreg/times.tsv
@@ -2760,7 +2760,6 @@
 2393	java/beans/PropertyEditor/TestEnumSubclassValue.java
 2392	java/util/PriorityQueue/RemoveContains.java
 2389	java/nio/MappedByteBuffer/ForceViews.java
-2389	java/math/BigInteger/BitLengthOverflow.java
 2389	java/io/Externalizable/compatibility/ExternalizableBlockData.java
 2386	java/security/cert/PKIXBuilderParameters/InvalidParameters.java
 2386	java/net/URL/RelativeURLTest.java