Changes for 1B vector benchmark

conf/cassandra-env.sh

@@ -188,7 +188,7 @@ if [ "$JVM_ARCH" = "64-Bit" ] && [ $USING_CMS -eq 0 ]; then
 fi
 
 # provides hints to the JIT compiler
-JVM_OPTS="$JVM_OPTS -XX:CompileCommandFile=$CASSANDRA_CONF/hotspot_compiler"
+JVM_OPTS="$JVM_OPTS -XX:CompileCommandFile=$CASSANDRA_CONF/hotspot_compiler -XX:+UnlockDiagnosticVMOptions -XX:CompilerDirectivesFile=$CASSANDRA_CONF/vector_hotspot_compiler"
 
 # add the jamm javaagent
 JVM_OPTS="$JVM_OPTS -javaagent:$CASSANDRA_HOME/lib/jamm-0.3.2.jar"

conf/cassandra.yaml

@@ -526,8 +526,8 @@ seed_provider:
 # On the other hand, since writes are almost never IO bound, the ideal
 # number of "concurrent_writes" is dependent on the number of cores in
 # your system; (8 * number_of_cores) is a good rule of thumb.
-concurrent_reads: 32
-concurrent_writes: 32
+concurrent_reads: 128
+concurrent_writes: 128
 concurrent_counter_writes: 32
 
 # For materialized view writes, as there is a read involved, so this should
@@ -573,8 +573,8 @@ concurrent_materialized_view_writes: 32
 # accepting writes when the limit is exceeded until a flush completes,
 # and will trigger a flush based on memtable_cleanup_threshold
 # If omitted, Cassandra will set both to 1/4 the size of the heap.
-# memtable_heap_space_in_mb: 2048
-# memtable_offheap_space_in_mb: 2048
+memtable_heap_space_in_mb: 8192
+memtable_offheap_space_in_mb: 32000
 
 # memtable_cleanup_threshold is deprecated. The default calculation
 # is the only reasonable choice. See the comments on  memtable_flush_writers
@@ -646,7 +646,7 @@ memtable_allocation_type: offheap_objects
 # The default value is the smaller of 8192, and 1/4 of the total space
 # of the commitlog volume.
 #
-# commitlog_total_space_in_mb: 8192
+commitlog_total_space_in_mb: 32000
 
 # This sets the number of memtable flush writer threads per disk
 # as well as the total number of memtables that can be flushed concurrently.
@@ -675,7 +675,7 @@ memtable_allocation_type: offheap_objects
 # and flush size and frequency. More is not better you just need enough flush writers
 # to never stall waiting for flushing to free memory.
 #
-#memtable_flush_writers: 2
+memtable_flush_writers: 8
 
 # Total space to use for change-data-capture logs on disk.
 #
@@ -918,7 +918,7 @@ column_index_cache_size_in_kb: 2
 #
 # If your data directories are backed by SSD, you should increase this
 # to the number of cores.
-#concurrent_compactors: 1
+concurrent_compactors: 64 
 
 # Number of simultaneous repair validations to allow. If not set or set to
 # a value less than 1, it defaults to the value of concurrent_compactors.
@@ -939,7 +939,7 @@ concurrent_materialized_view_builders: 1
 # Setting this to 0 disables throttling. Note that this accounts for all types
 # of compaction, including validation compaction (building Merkle trees
 # for repairs).
-compaction_throughput_mb_per_sec: 64
+compaction_throughput_mb_per_sec: 1000 
 
 # When compacting, the replacement sstable(s) can be opened before they
 # are completely written, and used in place of the prior sstables for
@@ -1499,6 +1499,9 @@ enable_drop_compact_storage: false
 #                 config value.
 # emulate_dbaas_defaults: false
 
+sai_options:
+  segment_write_buffer_space_mb: 1000
+
 # Guardrails settings.
 # guardrails:
   # When executing a scan, within or across a partition, we need to keep the

conf/jvm-server.options

@@ -115,7 +115,7 @@
 -XX:+UseNUMA
 
 # http://www.evanjones.ca/jvm-mmap-pause.html
--XX:+PerfDisableSharedMem
+#-XX:+PerfDisableSharedMem
 
 # Prefer binding to IPv4 network intefaces (when net.ipv6.bindv6only=1). See
 # http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6342561 (short version:
@@ -125,6 +125,12 @@
 # Disable chronicle analytics. See CASSANDRA-19656
 -Dchronicle.analytics.disable=true
 
+-Dunified_compaction.vector_sstable_growth=1 
+-Dunified_compaction.override_ucs_config_for_vector_tables=true
+
+-Dcassandra.sai.latest.version=ec
+-Dcassandra.sai.jvector_version=4
+-Dcassandra.sai_segment_builder_cores=96
 ### Debug options
 
 # uncomment to enable flight recorder
@@ -157,8 +163,8 @@
 # the same value to avoid stop-the-world GC pauses during resize, and
 # so that we can lock the heap in memory on startup to prevent any
 # of it from being swapped out.
-#-Xms4G
-#-Xmx4G
+-Xms128G
+-Xmx128G
 
 # Young generation size is automatically calculated by cassandra-env
 # based on this formula: min(100 * num_cores, 1/4 * heap size)

conf/vector_hotspot_compiler

@@ -0,0 +1,10 @@
+[
+  {
+    match: ["*.*"],
+    "inline": [
+// Third party library used for Vector Search https://github.com/jbellis/jvector
+      "+io.github.jbellis.jvector.vector.VectorUtil::*",
+      "+io.github.jbellis.jvector.vector.SimdOps::*"
+    ]
+  }
+]

src/java/org/apache/cassandra/index/sai/disk/v1/SegmentBuilder.java

@@ -78,8 +78,10 @@ public abstract class SegmentBuilder
 {
     private static final Logger logger = LoggerFactory.getLogger(SegmentBuilder.class);
 
+    private static final int NUM_THREADS = Integer.getInteger("cassandra.sai_segment_builder_cores", Runtime.getRuntime().availableProcessors());
+
     /** for parallelism within a single compaction */
-    public static final ExecutorService compactionExecutor = new DebuggableThreadPoolExecutor(Runtime.getRuntime().availableProcessors(),
+    public static final ExecutorService compactionExecutor = new DebuggableThreadPoolExecutor(NUM_THREADS,
                                                                                               1,
                                                                                               TimeUnit.MINUTES,
                                                                                               new ArrayBlockingQueue<>(10 * Runtime.getRuntime().availableProcessors()),

src/java/org/apache/cassandra/index/sai/disk/vector/CassandraOnHeapGraph.java

@@ -618,7 +618,7 @@ ProductQuantization computeOrRefineFrom(PqInfo existingInfo, VectorCompression p
             if (vectorValues.size() < MIN_PQ_ROWS)
                 return null;
             else
-                return ProductQuantization.compute(vectorValues, preferredCompression.getCompressedSize(), 256, false);
+                return ProductQuantization.compute(vectorValues, preferredCompression.getCompressedSize(), 128, false);
         }
 
         // use the existing one unmodified if we either don't have enough rows to fine-tune, or