Extremely large collection-*.wt file


Would appreciate some guidance. We’re running low on disk space on our local database disk. One of the collection*.wt files is extremely large (516G, representing ~90% of storage used). Is there a way to work out what it causing this to be so large?

In general, is there a way to measure the “footprint” of each project in the database?


Hi @arohou,

There’s not really a way to get the size of the database objects that correspond to all information in a project (without a complicated query, at least), but there is a way to see which collections inside the MongoDB database are taking up the most space. There is also a command you can run to release space back to the OS (MongoDB doesn’t do this automatically when documents are deleted).
See this post:

Thanks @stephan I shall try the compaction.

Do you have any tips in general on identifying, among a long list of projects, which are likely to have bigger footprints on the database?

Hi @arohou,

The collections in mongo that would take up the most amount of space are events and fs.files. Each job that’s created in a project stores its plots and text logs in those collections. There is not really an easy way to get the size of a query in the version of MongoDB that we’re running.