private void makeGlobalInfoCP() {
    long start = System.nanoTime();
    List<MemTableInfo> memTableInfos = activeOrPinnedMemTables();
    memTableInfos.removeIf(MemTableInfo::isFlushed);
    Checkpoint checkpoint = new Checkpoint(CheckpointType.GLOBAL_MEMORY_TABLE_INFO, memTableInfos);
    logByCachedByteBuffer(checkpoint);
    fsyncCheckpointFile();
    WRITING_METRICS.recordMakeCheckpointCost(checkpoint.getType(), System.nanoTime() - start);
  }
Make checkpoint for global memTables info, this checkpoint only exists in the beginning of each
checkpoint file.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/wal/checkpoint/CheckpointManager.java