Trying to speed up huge retrieval of data for web app.. separate cache?

I am working on a GPS system which uses EmberJS and Laravel.

We currently read all the IMEI's from a PgSQL DB, this is very time consuming and causes the load time of the application to be too slow for an application which one of it's main POI is real-time data.

Does this sound possible/feasible way of speeding this process up.. load all of the data into the cache using the IMEI of the device as its unique identifier.

The cache will run a check to see if any field has changed for a certain IMEI in the DB on a selected schedule. If it has then updated, then the data regarding the IMEI will be read and updated from the DB instantly.

The cache will then update the application constantly updating it every 30 seconds to or so.

So this would now read directly from cache upon application load not from the database although any updated information would come directly from there (any assets which are immobilised for example are a drain on resources).

If this idea is bad then why? and what alternative do you suggest?