When asking for the same index twice, the indexserver fails to find data for a small number of jobs

Asking the indexserver to make the same index twice, it seems to be unable to
find a small number of the data.

For an index of 1000, it fails to find data for 11 jobs, and for an index of 500 it fails to find data for 7 jobs.

This could be the reason for NAS-2118