Document 0 is too large for the cluster. generic mongodb:18

Question

Hi Folks,

one of my users is attempting to run a workflow which produces an error in the log file of

"Document 0 is too large for the cluster. Document is 31967054 bytes, max is 16777216.: generic server error"" code: <mongodb:18>"

Obviously he is not explicitly attempting to write to the Alteryx server MongoDB database and I guess he is going to re-write his code, but what would result in a large document of this size being written to the embedded Mono DB database?

Any suggestions?

CrumpN8or · Answer

Hi Steve,

this is a MongoDB specific error message, the largest single item that you can store in Mongo is 16MB. This is usually fine, as the average workflow is basically just a set of XML instructions on how to process your data. The data itself is pulled in, then spit out, so it is never needed to be saved in the MongoDB. From the message that you have copied, looks like your user's workflow is sized around 31Mb. This is pretty dang big for an alteryx workflow!

Most likely culprit is an item, text, table, etc. that is saved in the workflow as a text input, instead of being a data connection. With a data connection, the table could be on a shared network drive and pulled in only when needed. If the table is saved however as a text input, then Alteryx needs to encode and store that info in the workflow, which can make the size blow up quite quickly. In troubleshooting in this vein, I'd look for things that are embedded in the workflow rather than being referenced. More examples could include Jupyter notebooks for running code, or an image/watermark/logo that gets appended to a report.

Good luck and let us know what you find!

Matt Crump

Aimpoint Digital

patrick_mcauliffe · Answer

There are many possibilities.
Can you provide more information about the workflow?
What is it doing?  What are the inputs?  What are the outputs?