How to save assets fast (AssetDatabase.CreateAsset)

I have generated about 70 000 gameobjects with meshes and materials in a scene. I need to save these meshes and materials in assets. I save assets with AssetDatabase.CreateAsset, but its takes a lot of time (Save 10k meshes takes about 3.5 hours). I save meshes and materials in order to make bundles.

My code generate meshes and materials:

  public class SaveAssetsUtils
 {
 static public void Save(string path, GameObject target)
 {
     if (!Directory.Exists(path))
         Directory.CreateDirectory(path);
 
     string materialsPathBase = path + "Materials/";
     string meshesPathBase = path + "Meshes/";
 
     if (!Directory.Exists(materialsPathBase))
         Directory.CreateDirectory(materialsPathBase);
     else
         FilesUtils.ClearFolder(materialsPathBase);
 
     int folderIndex = 0;
     string meshesDir = "dir" + folderIndex + "/";
     if (!Directory.Exists(meshesPathBase))
         Directory.CreateDirectory(meshesPathBase);
     else
         FilesUtils.ClearFolder(meshesPathBase);
 
     if (!Directory.Exists(meshesPathBase + meshesDir))
         Directory.CreateDirectory(meshesPathBase + meshesDir);
 
     MeshFilter[] meshFilters = target.GetComponentsInChildren<MeshFilter>(true);
 
     ProgressUtil.Progress("Starting save assets", "starting save assets " + meshFilters.Length, 0.323f);
 
     int indexMesh = 0;
     int indexMaterial = 0;
     int countMeshes = 0;
 
     int count = meshFilters.Length;
 
     for (int i = 0; i < meshFilters.Length; i++)
     {
         var meshFilter = meshFilters[i];
         var meshRenderer = meshFilter.gameObject.GetComponent<MeshRenderer>();
 
         var materialName = meshRenderer.sharedMaterial.name;
         if (materialName.IndexOf("exists") == -1)
         {
             var pathMaterial = materialsPathBase + "_exists_" + indexMaterial + ".mat";
 
             meshRenderer.sharedMaterial.name = "_exists_" + indexMaterial;
             UnityEditor.AssetDatabase.CreateAsset(meshRenderer.sharedMaterial, pathMaterial);
 
             indexMaterial++;
         }
 
         var meshName = meshFilter.sharedMesh.name;
         if (meshName.IndexOf("exists") == -1)
         {
             ProgressUtil.Progress("Save mesh", "save mesh " + indexMesh + " from " + meshFilters.Length, 0.323f + (0.68f / count) * indexMesh );
 
             var pathMesh = meshesPathBase + meshesDir + "_exists_" + i + ".asset";
 
             meshFilter.sharedMesh.name = "_exists_" + indexMesh;
             UnityEditor.AssetDatabase.CreateAsset(meshFilter.sharedMesh, pathMesh);
 
             indexMesh++;
             countMeshes++;
         }
 
         if (countMeshes > 100)
         {
             folderIndex++;
             countMeshes = 0;
             meshesDir = "dir" + folderIndex + "/";
             if (!Directory.Exists(meshesPathBase + meshesDir))
                 Directory.CreateDirectory(meshesPathBase + meshesDir);
         }
     }
 
     UnityEditor.AssetDatabase.SaveAssets();
 }