Dataloader slows performance considerably.

[woh-dev]

Are there any setup mistakes that I could be making that would result in Dataloader causing a massive performance hit for queries?

For the below query I am seeing average response times of 350ms without Dataloader and a huge increase to 5.9s - 11s with Dataloader:

query{
  userChats {
    _id
    participants {
      user {
        _id
        username
      }
    }
    buckets(last: 1) {
      edges {
        node {
          _id
          messages {
            author {
              name                        // the author field 'refs' the user collection 
            }
            text
            contentType
            systemMsg
            album {
              user {
                _id
                name
              }
              images {
                medium {
                  url
                }
              }
            }
            website {
              user {
                _id
                name
              }
              caption
              images {
                medium {
                  url
                }
              }
            }
            post {
              user {
                name
              }
              caption
              images {
                medium {
                  url
                }
              }
            }
            list {
              _id
              _teaser {
                large {
                  _sourceImage
                }
              }
            }
          }
        }
      }
    }
  }
}

I am setting up Dataloader by wrapping each TC composeWithDataLoader() and I'm not setting any options for cacheExpiration or removeProjection.

When I enable debug I see the following for the above query

New db request (findMany)
New db request (findOne)
New db request (connection)
New db request (findOne)
New db request (findOne)
New db request (findOne)
New db request (findOne)
New db request (findOne)
New db request (findOne)
New db request (findOne)
New db request (findOne)
New db request (findOne)
New db request (findOne)
New db request (findOne)

Any thoughts on what I might be doing wrong here or where to continue debugging?

I would expect that this kind of query would represent HUGE performance gains via dataloader given that we are loading the same user records over and over for each chat message.

[Marcvander]

I'm having the exact same problem. I'm wrapping composeWithDataLoader() around my composeWithMongoose() (composeWithDataLoader(composeWithMongoose(HumanAssignment))) and it considerably slows down my request

[SnidelyWhiplash]

Hello, is there any update here? Thanks!

[ddzyan]

I also encountered this problem