Consider reusing active buffer.

3 files changed, 45 insertions, 15 deletions

diff --git a/vespalib/src/tests/datastore/array_store/array_store_test.cpp b/vespalib/src/tests/datastore/array_store/array_store_test.cpp
index 417d8b80d87..562ecaaecfa 100644
--- a/vespalib/src/tests/datastore/array_store/array_store_test.cpp
+++ b/vespalib/src/tests/datastore/array_store/array_store_test.cpp
@@ -150,13 +150,13 @@ TEST("require that we test with trivial and non-trivial types")
 
 TEST_F("control static sizes", NumberFixture(3)) {
 #ifdef _LIBCPP_VERSION
-    EXPECT_EQUAL(400u, sizeof(f.store));
+    EXPECT_EQUAL(424u, sizeof(f.store));
     EXPECT_EQUAL(296u, sizeof(NumberFixture::ArrayStoreType::DataStoreType));
 #else
-    EXPECT_EQUAL(432u, sizeof(f.store));
+    EXPECT_EQUAL(456u, sizeof(f.store));
     EXPECT_EQUAL(328u, sizeof(NumberFixture::ArrayStoreType::DataStoreType));
 #endif
-    EXPECT_EQUAL(72u, sizeof(NumberFixture::ArrayStoreType::SmallArrayType));
+    EXPECT_EQUAL(96u, sizeof(NumberFixture::ArrayStoreType::SmallArrayType));
     MemoryUsage usage = f.store.getMemoryUsage();
     EXPECT_EQUAL(960u, usage.allocatedBytes());
     EXPECT_EQUAL(32u, usage.usedBytes());
diff --git a/vespalib/src/tests/datastore/buffer_type/buffer_type_test.cpp b/vespalib/src/tests/datastore/buffer_type/buffer_type_test.cpp
index 414c35864ac..4cd192f602f 100644
--- a/vespalib/src/tests/datastore/buffer_type/buffer_type_test.cpp
+++ b/vespalib/src/tests/datastore/buffer_type/buffer_type_test.cpp
@@ -49,7 +49,7 @@ struct Fixture {
     }
     ~Fixture() {
         for (auto& setup : setups) {
-            bufferType.onHold(&setup._usedElems, &setup._deadElems);
+            bufferType.onHold(setup._bufferId, &setup._usedElems, &setup._deadElems);
             bufferType.onFree(setup._usedElems);
         }
     }
@@ -134,9 +134,9 @@ TEST("arrays to alloc considers used elements across all active buffers of same
 {
     Fixture f(Setup().used(6 * 4));
     f.assertArraysToAlloc(6 * 0.5);
-    f.add_setup(Setup().used(8 * 4));
+    f.add_setup(Setup().used(8 * 4).bufferId(2));
     f.assertArraysToAlloc((6 + 8) * 0.5);
-    f.add_setup(Setup().used(10 * 4));
+    f.add_setup(Setup().used(10 * 4).bufferId(3));
     f.assertArraysToAlloc((6 + 8 + 10) * 0.5);
 }
 
@@ -144,7 +144,7 @@ TEST("arrays to alloc considers used elements across all active buffers of same
 {
     Fixture f(Setup().used(6 * 4));
     f.assertArraysToAlloc(6 * 0.5);
-    f.add_setup(Setup().used(8 * 4).resizing(true));
+    f.add_setup(Setup().used(8 * 4).resizing(true).bufferId(2));
     f.assertArraysToAlloc(8 + (6 + 8) * 0.5);
 }
 
@@ -152,9 +152,9 @@ TEST("arrays to alloc considers (and subtracts) dead elements across all active
 {
     Fixture f(Setup().used(6 * 4).dead(2 * 4));
     f.assertArraysToAlloc((6 - 2) * 0.5);
-    f.add_setup(Setup().used(12 * 4).dead(4 * 4));
+    f.add_setup(Setup().used(12 * 4).dead(4 * 4).bufferId(2));
     f.assertArraysToAlloc((6 - 2 + 12 - 4) * 0.5);
-    f.add_setup(Setup().used(20 * 4).dead(6 * 4));
+    f.add_setup(Setup().used(20 * 4).dead(6 * 4).bufferId(3));
     f.assertArraysToAlloc((6 - 2 + 12 - 4 + 20 - 6) * 0.5);
 }
 
@@ -162,7 +162,7 @@ TEST("arrays to alloc considers (and subtracts) dead elements across all active
 {
     Fixture f(Setup().used(6 * 4).dead(2 * 4));
     f.assertArraysToAlloc((6 - 2) * 0.5);
-    f.add_setup(Setup().used(12 * 4).dead(4 * 4).resizing(true));
+    f.add_setup(Setup().used(12 * 4).dead(4 * 4).resizing(true).bufferId(2));
     f.assertArraysToAlloc(12 + (6 - 2 + 12 - 4) * 0.5);
 }
 
diff --git a/vespalib/src/tests/datastore/datastore/datastore_test.cpp b/vespalib/src/tests/datastore/datastore/datastore_test.cpp
index 548ab9199da..1c4817ea35f 100644
--- a/vespalib/src/tests/datastore/datastore/datastore_test.cpp
+++ b/vespalib/src/tests/datastore/datastore/datastore_test.cpp
@@ -55,6 +55,7 @@ public:
 
 
 using GrowthStats = std::vector<int>;
+using BufferStats = std::vector<int>;
 
 constexpr float ALLOC_GROW_FACTOR = 0.4;
 constexpr size_t HUGE_PAGE_ARRAY_SIZE = (MemoryAllocator::HUGEPAGE_SIZE / sizeof(int));
@@ -123,6 +124,19 @@ public:
             ++i;
         }
     }
+    BufferStats getBuffers(size_t bufs) {
+        BufferStats buffers;
+        while (buffers.size() < bufs) {
+            RefType iRef = (_type.getArraySize() == 1) ?
+                           (_store.template allocator<DataType>(_typeId).alloc().ref) :
+                           (_store.template allocator<DataType>(_typeId).allocArray(_type.getArraySize()).ref);
+            int buffer_id = iRef.bufferId();
+            if (buffers.empty() || buffers.back() != buffer_id) {
+                buffers.push_back(buffer_id);
+            }
+        }
+        return buffers;
+    }
     vespalib::MemoryUsage getMemoryUsage() const { return _store.getMemoryUsage(); }
 };
 
@@ -563,7 +577,7 @@ TEST(DataStoreTest, require_that_buffer_growth_works)
     assertGrowStats({ 4, 4, 4, 4, 8, 16, 16, 32, 64, 64 },
                     { 4 }, 20, 4, 0);
     // Resize if buffer size is less than 4, min size 0
-    assertGrowStats({ 4, 4, 8, 32, 32, 32, 64, 128, 128, 128 },
+    assertGrowStats({ 4, 4, 8, 32, 32, 64, 64, 128, 128, 128 },
                     { 0, 1, 2, 4 }, 4, 0, 4);
     // Always switch to new buffer, min size 16
     assertGrowStats({ 16, 16, 16, 32, 32, 64, 128, 128, 128 },
@@ -580,7 +594,7 @@ TEST(DataStoreTest, require_that_buffer_growth_works)
 
     // Buffers with sizes larger than the huge page size of the mmap allocator.
     ASSERT_EQ(524288u, HUGE_PAGE_ARRAY_SIZE);
-    assertGrowStats({ 262144, 524288, 524288, 524288 * 3, 524288 * 3, 524288 * 4, 524288 * 5, 524288 * 5, 524288 * 5, 524288 * 5 },
+    assertGrowStats({ 262144, 524288, 524288, 524288 * 3, 524288 * 3, 524288 * 5, 524288 * 5, 524288 * 5, 524288 * 5, 524288 * 5 },
                     { 0, 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536, 131072, 262144 },
                     4, 0, HUGE_PAGE_ARRAY_SIZE / 2, HUGE_PAGE_ARRAY_SIZE * 5);
 }
@@ -615,10 +629,10 @@ TEST(DataStoreTest, require_that_offset_in_EntryRefT_is_within_bounds_when_alloc
      *      The max bytes to alloc is: maxArrays * arraySize * elementSize.
      */
     assertGrowStats<uint8_t>({8192,16384,16384,65536,65536,98304,98304,98304,98304,98304,98304,98304}, 3);
-    assertGrowStats<uint8_t>({16384,16384,65536,65536,65536,131072,163840,163840,163840,163840,163840,163840}, 5);
+    assertGrowStats<uint8_t>({16384,16384,65536,65536,131072,131072,163840,163840,163840,163840,163840,163840}, 5);
     assertGrowStats<uint8_t>({16384,32768,32768,131072,131072,229376,229376,229376,229376,229376,229376,229376}, 7);
     assertGrowStats<uint32_t>({8192,16384,16384,65536,65536,98304,98304,98304,98304,98304,98304,98304}, 3);
-    assertGrowStats<uint32_t>({16384,16384,65536,65536,65536,131072,163840,163840,163840,163840,163840,163840}, 5);
+    assertGrowStats<uint32_t>({16384,16384,65536,65536,131072,131072,163840,163840,163840,163840,163840,163840}, 5);
     assertGrowStats<uint32_t>({16384,32768,32768,131072,131072,229376,229376,229376,229376,229376,229376,229376}, 7);
 }
 
@@ -666,8 +680,24 @@ TEST(DataStoreTest, can_set_memory_allocator)
     EXPECT_EQ(AllocStats(3, 3), stats);
 }
 
+namespace {
+
+void
+assertBuffers(BufferStats exp_buffers, size_t num_arrays_for_new_buffer)
+{
+    EXPECT_EQ(exp_buffers, IntGrowStore(1, 1, 1024, num_arrays_for_new_buffer).getBuffers(exp_buffers.size()));
+}
+
+}
+
+TEST(DataStoreTest, can_reuse_active_buffer_as_primary_buffer)
+{
+    assertBuffers({ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11}, 0);
+    assertBuffers({ 1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3}, 16);
+}
+
 TEST(DataStoreTest, control_static_sizes) {
-    EXPECT_EQ(72, sizeof(BufferTypeBase));
+    EXPECT_EQ(96, sizeof(BufferTypeBase));
     EXPECT_EQ(32, sizeof(BufferState::FreeList));
     EXPECT_EQ(1, sizeof(BufferState::State));
     EXPECT_EQ(144, sizeof(BufferState));