Wasm buffer manager support

extension/json/test/doc_examples.test

@@ -1,4 +1,5 @@
 -DATASET CSV empty
+-BUFFER_POOL_SIZE 134217728
 
 --
 

extension/json/test/error.test

@@ -1,4 +1,5 @@
 -DATASET CSV empty
+-BUFFER_POOL_SIZE 268435456
 
 --
 

src/include/common/constants.h

@@ -84,7 +84,7 @@ struct BufferPoolConstants {
 #else
     static constexpr uint64_t DEFAULT_VM_REGION_MAX_SIZE = static_cast<uint64_t>(1) << 43; // (8TB)
 #endif
-    static constexpr uint64_t DEFAULT_BUFFER_POOL_SIZE_FOR_TESTING = 1ull << 28; // (256MB)
+    static constexpr uint64_t DEFAULT_BUFFER_POOL_SIZE_FOR_TESTING = 1ull << 26; // (64MB)
 };
 
 struct StorageConstants {

src/include/storage/buffer_manager/buffer_manager.h

@@ -7,6 +7,8 @@
 #include <vector>
 
 #include "common/types/types.h"
+#include "storage/buffer_manager/memory_manager.h"
+#include "storage/buffer_manager/page_state.h"
 #include "storage/enums/page_read_policy.h"
 #include "storage/file_handle.h"
 
@@ -222,10 +224,19 @@ class BufferManager {
     // The function assumes that the requested page is already pinned.
     void unpin(FileHandle& fileHandle, common::page_idx_t pageIdx);
     uint8_t* getFrame(FileHandle& fileHandle, common::page_idx_t pageIdx) const {
+#if BM_MALLOC
+        return fileHandle.getPageState(pageIdx)->getPage();
+#else
         return vmRegions[fileHandle.getPageSizeClass()]->getFrame(fileHandle.getFrameIdx(pageIdx));
+#endif
     }
-    common::frame_group_idx_t addNewFrameGroup(common::PageSizeClass pageSizeClass) {
+    common::frame_group_idx_t addNewFrameGroup(
+        common::PageSizeClass pageSizeClass [[maybe_unused]]) {
+#if BM_MALLOC
+        return 0;
+#else
         return vmRegions[pageSizeClass]->addNewFrameGroup();
+#endif
     }
     void removePageFromFrameIfNecessary(FileHandle& fileHandle, common::page_idx_t pageIdx);
 
@@ -242,8 +253,13 @@ class BufferManager {
 
     uint64_t freeUsedMemory(uint64_t size);
 
-    void releaseFrameForPage(FileHandle& fileHandle, common::page_idx_t pageIdx) {
+    void releaseFrameForPage(FileHandle& fileHandle [[maybe_unused]],
+        common::page_idx_t pageIdx [[maybe_unused]]) {
+#if BM_MALLOC
+        // Page is freed instead in PageState::resetToEvicted
+#else
         vmRegions[fileHandle.getPageSizeClass()]->releaseFrame(fileHandle.getFrameIdx(pageIdx));
+#endif
     }
 
     uint64_t evictPages();
@@ -257,7 +273,7 @@ class BufferManager {
     std::atomic<uint64_t> nonEvictableMemory;
     // Each VMRegion corresponds to a virtual memory region of a specific page size. Currently, we
     // hold two sizes of REGULAR_PAGE and TEMP_PAGE.
-    std::vector<std::unique_ptr<VMRegion>> vmRegions;
+    std::array<std::unique_ptr<VMRegion>, 2> vmRegions;
     std::vector<std::unique_ptr<FileHandle>> fileHandles;
     std::unique_ptr<Spiller> spiller;
     common::VirtualFileSystem* vfs;

src/include/storage/buffer_manager/page_state.h

@@ -4,6 +4,13 @@
 
 #include "common/assert.h"
 
+// Alternative variant of the buffer manager which doesn't rely on MADV_DONTNEED (on Unix) for
+// evicting pages (which is unavailable in Webassembly runtimes)
+#define BM_MALLOC __WASM__
+#if BM_MALLOC
+#include <memory>
+#endif
+
 namespace kuzu {
 namespace storage {
 
@@ -74,12 +81,28 @@ class PageState {
     bool isDirty() const { return stateAndVersion & DIRTY_MASK; }
     uint64_t getStateAndVersion() const { return stateAndVersion.load(); }
 
-    void resetToEvicted() { stateAndVersion.store(EVICTED << NUM_BITS_TO_SHIFT_FOR_STATE); }
+    void resetToEvicted() {
+        stateAndVersion.store(EVICTED << NUM_BITS_TO_SHIFT_FOR_STATE);
+#if BM_MALLOC
+        page.reset();
+#endif
+    }
+
+#if BM_MALLOC
+    uint8_t* getPage() const { return page.get(); }
+    uint8_t* allocatePage(uint64_t pageSize) {
+        page = std::make_unique<uint8_t[]>(pageSize);
+        return page.get();
+    }
+#endif
 
 private:
     // Highest 1 bit is dirty bit, and the rest are page state and version bits.
     // In the rest bits, the lowest 1 byte is state, and the rest are version.
     std::atomic<uint64_t> stateAndVersion;
+#if BM_MALLOC
+    std::unique_ptr<uint8_t[]> page;
+#endif
 };
 
 } // namespace storage

src/storage/buffer_manager/buffer_manager.cpp

@@ -84,9 +84,10 @@ BufferManager::BufferManager(const std::string& databasePath, const std::string&
     : bufferPoolSize{bufferPoolSize}, evictionQueue{bufferPoolSize / KUZU_PAGE_SIZE},
       usedMemory{evictionQueue.getCapacity() * sizeof(EvictionCandidate)}, vfs{vfs} {
     verifySizeParams(bufferPoolSize, maxDBSize);
-    vmRegions.resize(2);
+#if !BM_MALLOC
     vmRegions[0] = std::make_unique<VMRegion>(REGULAR_PAGE, maxDBSize);
     vmRegions[1] = std::make_unique<VMRegion>(TEMP_PAGE, bufferPoolSize);
+#endif
 
     // TODO(bmwinger): It may be better to spill to disk in a different location for remote file
     // systems, or even in general.
@@ -141,7 +142,12 @@ uint8_t* BufferManager::pin(FileHandle& fileHandle, page_idx_t pageIdx,
                     throw BufferManagerException(
                         "Eviction queue is full! This should be impossible.");
                 }
+#if BM_MALLOC
+                KU_ASSERT(pageState->getPage());
+                return pageState->getPage();
+#else
                 return getFrame(fileHandle, pageIdx);
+#endif
             }
         } break;
         case PageState::UNLOCKED:
@@ -193,12 +199,19 @@ void handleAccessViolation(unsigned int exceptionCode, PEXCEPTION_POINTERS excep
 
 // Returns true if the function completes successfully
 inline bool try_func(const std::function<void(uint8_t*)>& func, uint8_t* frame,
-    const std::vector<std::unique_ptr<VMRegion>>& vmRegions, PageSizeClass pageSizeClass) {
-#if defined(_WIN32)
+    const std::array<std::unique_ptr<VMRegion>, 2>& vmRegions [[maybe_unused]],
+    PageSizeClass pageSizeClass [[maybe_unused]]) {
+#if BM_MALLOC
+    if (frame == nullptr) {
+        return false;
+    }
+#endif
+
+#if defined(_WIN32) && !BM_MALLOC
     try {
 #endif
         func(frame);
-#if defined(_WIN32)
+#if defined(_WIN32) && !BM_MALLOC
     } catch (AccessViolation& exc) {
         // If we encounter an acess violation within the VM region,
         // the page was decomitted by another thread
@@ -209,9 +222,6 @@ inline bool try_func(const std::function<void(uint8_t*)>& func, uint8_t* frame,
             throw EXCEPTION_ACCESS_VIOLATION;
         }
     }
-#else
-    (void)pageSizeClass;
-    (void)vmRegions;
 #endif
     return true;
 }
@@ -309,8 +319,7 @@ bool BufferManager::claimAFrame(FileHandle& fileHandle, page_idx_t pageIdx,
     if (!reserve(pageSizeToClaim)) {
         return false;
     }
-#ifdef _WIN32
-    // We need to commit memory explicitly on Windows.
+#if _WIN32 && !BM_MALLOC
     // Committing in this context means reserving physical memory/page file space for a segment of
     // virtual memory. On Linux/Unix this is automatic when you write to the memory address.
     auto result =
@@ -408,9 +417,16 @@ void BufferManager::cachePageIntoFrame(FileHandle& fileHandle, page_idx_t pageId
     PageReadPolicy pageReadPolicy) {
     auto pageState = fileHandle.getPageState(pageIdx);
     pageState->clearDirty();
+#if BM_MALLOC
+    pageState->allocatePage(fileHandle.getPageSize());
+    if (pageReadPolicy == PageReadPolicy::READ_PAGE) {
+        fileHandle.readPageFromDisk(pageState->getPage(), pageIdx);
+    }
+#else
     if (pageReadPolicy == PageReadPolicy::READ_PAGE) {
         fileHandle.readPageFromDisk(getFrame(fileHandle, pageIdx), pageIdx);
     }
+#endif
 }
 
 void BufferManager::removeFilePagesFromFrames(FileHandle& fileHandle) {

test/test_files/copy/copy_after_error.test

@@ -1,4 +1,5 @@
 -DATASET CSV empty
+-BUFFER_POOL_SIZE 268435456
 --
 
 -CASE CopyNodeAfterError

test/test_files/dml_rel/create/create_ldbc_sf01.test

@@ -1,4 +1,6 @@
 -DATASET CSV ldbc-sf01
+-BUFFER_POOL_SIZE 134217728
+
 --
 
 -CASE CreateLikeComment

test/test_files/dml_rel/delete/delete_ldbc_sf01.test

@@ -1,4 +1,5 @@
 -DATASET CSV ldbc-sf01
+-BUFFER_POOL_SIZE 134217728
 --
 
 -CASE DeleteLikeComment1

test/test_files/dml_rel/set/set_ldbc_sf01.test

@@ -1,4 +1,5 @@
 -DATASET CSV ldbc-sf01
+-BUFFER_POOL_SIZE 134217728
 --
 
 -CASE SetLikeComment

test/test_files/issue/issue5.test

@@ -1,4 +1,5 @@
 -DATASET CSV ldbc-sf01
+-BUFFER_POOL_SIZE 134217728
 
 --
 
@@ -18,4 +19,4 @@
 ---- ok
 -STATEMENT MATCH (a:Person)-[r:knows_with_null]->(b:Person) WHERE r.__EXTRAID IS NOT NULL RETURN COUNT(*)
 ---- 1
-0
+0

test/test_files/tck/match/match7.test

@@ -1,4 +1,5 @@
 -DATASET CSV tck
+-BUFFER_POOL_SIZE 268435456
 
 --