BuddyChunkController Class — netty Architecture

Source Code

buffer/src/main/java/io/netty/buffer/AdaptivePoolingAllocator.java lines 756–785

    private static final class BuddyChunkController implements ChunkController {
        private final ChunkAllocator chunkAllocator;
        private final ChunkRegistry chunkRegistry;
        private final AtomicInteger maxChunkSize;

        BuddyChunkController(MagazineGroup group, AtomicInteger maxChunkSize) {
            chunkAllocator = group.chunkAllocator;
            chunkRegistry = group.allocator.chunkRegistry;
            this.maxChunkSize = maxChunkSize;
        }

        @Override
        public int computeBufferCapacity(int requestedSize, int maxCapacity, boolean isReallocation) {
            return MathUtil.safeFindNextPositivePowerOfTwo(requestedSize);
        }

        @Override
        public Chunk newChunkAllocation(int promptingSize, Magazine magazine) {
            int maxChunkSize = this.maxChunkSize.get();
            int proposedChunkSize = MathUtil.safeFindNextPositivePowerOfTwo(BUFS_PER_CHUNK * promptingSize);
            int chunkSize = Math.min(MAX_CHUNK_SIZE, Math.max(maxChunkSize, proposedChunkSize));
            if (chunkSize > maxChunkSize) {
                // Update our stored max chunk size. It's fine that this is racy.
                this.maxChunkSize.set(chunkSize);
            }
            BuddyChunk chunk = new BuddyChunk(chunkAllocator.allocate(chunkSize, chunkSize), magazine);
            chunkRegistry.add(chunk);
            return chunk;
        }
    }