We have an index that get ~15M documents a day, each with a epoch milliseconds timestamp.
Date aggregations seems to work fine, but the bigger the index - the longer the query.
One action would be to separate the index per day, which will allow us flexibility and much better performance.
Another idea was to "round" the milliseconds timestamp into minutes, so instead of each mseconds, it will be indexed in its minute-related msecond.
My question is - would it make performance better ?
Considering the related field index would be much smaller (x60000 smaller) - would it make the query faster ?
I failed to find any example like that, nor recommendation for such an action.