A billion events is only ~4GB on disk. With disk so cheap (even now), why throw that away immediately instead of at least waiting 30 days, 1 year, etc. until you know you have your analysis right?
That's a fair point, and honestly disk cost rarely is the blocker these days. ~4GB assumes a few bytes per event, in our case it is closer to 100GB a day. That would be stored as raw text. Being able to rebuild that would require us to have some kind of pipeline that can do that effectively and that kind of defeats the point of Trifle.
That said, it really depends on the use case. For us the last 24h-48h holds the most value and anything older than that is just a reference where margin of error is acceptable. Even if we correct the historical data from 2 weeks ago, it wouldn't change the decisions we make today. For others it may be the opposite.
Tbh nothing stops you from doing both. Trifle is just a library that writes into your own database. If your data requires occasional re-analysis, write them into their own events table. Then you have the ability to rebuild the stats as you need to. I've seen both sides of the table, and as Trifle code lives with the rest of the code, it is simpler to handle this yourself than try to do this somehow via the App (which is optional in the first place) and UI.
A billion events is only ~4GB on disk. With disk so cheap (even now), why throw that away immediately instead of at least waiting 30 days, 1 year, etc. until you know you have your analysis right?
That's a fair point, and honestly disk cost rarely is the blocker these days. ~4GB assumes a few bytes per event, in our case it is closer to 100GB a day. That would be stored as raw text. Being able to rebuild that would require us to have some kind of pipeline that can do that effectively and that kind of defeats the point of Trifle.
That said, it really depends on the use case. For us the last 24h-48h holds the most value and anything older than that is just a reference where margin of error is acceptable. Even if we correct the historical data from 2 weeks ago, it wouldn't change the decisions we make today. For others it may be the opposite.
Tbh nothing stops you from doing both. Trifle is just a library that writes into your own database. If your data requires occasional re-analysis, write them into their own events table. Then you have the ability to rebuild the stats as you need to. I've seen both sides of the table, and as Trifle code lives with the rest of the code, it is simpler to handle this yourself than try to do this somehow via the App (which is optional in the first place) and UI.