diff --git a/x-pack/plugin/snapshot-repo-test-kit/qa/s3/src/javaRestTest/java/org/elasticsearch/repositories/blobstore/testkit/analyze/S3RepositoryAnalysisRestIT.java b/x-pack/plugin/snapshot-repo-test-kit/qa/s3/src/javaRestTest/java/org/elasticsearch/repositories/blobstore/testkit/analyze/S3RepositoryAnalysisRestIT.java
index c0f2b40f5a10f..e5930e02375b7 100644
--- a/x-pack/plugin/snapshot-repo-test-kit/qa/s3/src/javaRestTest/java/org/elasticsearch/repositories/blobstore/testkit/analyze/S3RepositoryAnalysisRestIT.java
+++ b/x-pack/plugin/snapshot-repo-test-kit/qa/s3/src/javaRestTest/java/org/elasticsearch/repositories/blobstore/testkit/analyze/S3RepositoryAnalysisRestIT.java
@@ -9,6 +9,7 @@
 import fixture.s3.S3HttpFixture;
 
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.common.unit.ByteSizeValue;
 import org.elasticsearch.test.cluster.ElasticsearchCluster;
 import org.elasticsearch.test.cluster.local.distribution.DistributionType;
 import org.junit.ClassRule;
@@ -59,6 +60,7 @@ protected Settings repositorySettings() {
             .put("bucket", bucket)
             .put("base_path", basePath)
             .put("delete_objects_max_size", between(1, 1000))
+            .put("buffer_size", ByteSizeValue.ofMb(5)) // so some uploads are multipart ones
             .build();
     }
 }
diff --git a/x-pack/plugin/snapshot-repo-test-kit/src/test/java/org/elasticsearch/repositories/blobstore/testkit/analyze/AbstractRepositoryAnalysisRestTestCase.java b/x-pack/plugin/snapshot-repo-test-kit/src/test/java/org/elasticsearch/repositories/blobstore/testkit/analyze/AbstractRepositoryAnalysisRestTestCase.java
index 2c96003f7e3d3..a971772975128 100644
--- a/x-pack/plugin/snapshot-repo-test-kit/src/test/java/org/elasticsearch/repositories/blobstore/testkit/analyze/AbstractRepositoryAnalysisRestTestCase.java
+++ b/x-pack/plugin/snapshot-repo-test-kit/src/test/java/org/elasticsearch/repositories/blobstore/testkit/analyze/AbstractRepositoryAnalysisRestTestCase.java
@@ -29,7 +29,7 @@ public void testRepositoryAnalysis() throws Exception {
         final Request request = new Request(HttpPost.METHOD_NAME, "/_snapshot/" + repository + "/_analyze");
         request.addParameter("blob_count", "10");
         request.addParameter("concurrency", "4");
-        request.addParameter("max_blob_size", "1mb");
+        request.addParameter("max_blob_size", randomFrom("1mb", "10mb"));
         request.addParameter("timeout", "120s");
         request.addParameter("seed", Long.toString(randomLong()));
         assertOK(client().performRequest(request));