         do {
             try self.fileManager.createDirectoryAtPath(root, withIntermediateDirectories: true, attributes: nil)
         } catch {
-            NSLog("fail to create cache group %@, error = %@", url, error as NSError)
+            let error = error as NSError
+            if error.domain == NSCocoaErrorDomain && error.code != 516 {
+                NSLog("fail to create cache group %@, error = %@", url, error)
+            }
         }
     }
     

            _ = try? self.fileManager.removeItemAtPath(self.root)
            try self.fileManager.createDirectoryAtPath(self.root, withIntermediateDirectories: true, attributes: nil)
        } catch {
            NSLog("fail to init cache root, error = %@", error as NSError)
        }
    }
}

            self.root = root.hasSuffix("/") ? root : root + "/"
            try self.fileManager.createDirectoryAtPath(self.root, withIntermediateDirectories: true, attributes: nil)
        } catch {
            let error = error as NSError
            if error.domain == NSCocoaErrorDomain && error.code != 516 {
                NSLog("fail to create cache directory, error = %@", error)
            }
        }
    }

