Enable sar by default in cassandra and increase compaction wait retries

PiperOrigin-RevId: 884643317

Author: Arushi-07

perfkitbenchmarker/configs/default_benchmark_config.yaml

@@ -691,6 +691,9 @@ cassandra_stress_mixed_workload:
   flags:
     cassandra_stress_mixed_ratio: 'write=3,read=1'
     cassandra_stress_command: 'mixed'
+    cassandra_compaction_throughput_mb: 250
+    cassandra_stress_preload_num_keys: 550000000  # 550000000 preload keys are writing ~140G of data to the disk. The dataset size needs to be 5 times the VM memory and 8 vCPU standard machines usually have around 30G memory.
+    cassandra_stress_population_size: 550000000
 
 nginx_network_saturated_workload:
   name: nginx

perfkitbenchmarker/linux_benchmarks/cassandra_stress_benchmark.py

@@ -326,6 +326,7 @@
     db_disk_type: hypderdisk-balanced
     db_disk_size: 350
     openjdk_version: 17
+    sar: True
 """
 
 CASSANDRA_GROUP = 'workers'
@@ -1203,7 +1204,7 @@ def RunCassandraStress(
 
 
 @vm_util.Retry(
-    max_retries=20,
+    max_retries=40,
     retryable_exceptions=(CassandraCompactionNotCompletedError,),
     poll_interval=WAIT_BETWEEN_COMPACTION_TASKS_CHECK,
     timeout=-1,