In WT-7607, different db were uploaded to the cloud in order to skip the populating phase in the many-coll-test.

However, it appeared that populating the database was faster than downloading a prepopulated and started the mongod process on it. This does not seem right and needs investigation.

The slow startup of mongodb has been confirmed on the following versions of MongoDB : 5.0.0-rc4 and 4.4.3

One suggestion would be to upload the database again making sure the database was closed correctly and see if it helps. (See comments below, it did not change anything)

Once this issue is resolved, we should download a pre-populated database in our many-collection-test task instead of creating one every time.