> But when responding to a PagerDuty alert, the first thing I want to see is a plot of the alerting series. When you do receive a page, you can then hit a data

> But when responding to a PagerDuty alert, the first thing I want to see is a plot of the alerting series. When you do receive a page, you can then hit a database. This happens rarely enough (hopefully!) so that your database can be optimised for writes only, not for writes and reads, as $parent suggested. I would even argue that this is a similar use case than dashboarding: when paged you want to see the last 3 days or so of accurate data + some longer term averages/trends/baseline. All of this could fit in RAM. At least in the current prototype I mentioned above the ambition is to be able to serve recent data for such dashboards out of RAM without bothering with a DB, and have the DB completely out of the way for the monitoring use case (while still having a persistent store for long term capacity planning / business analyses). Assuming doubles are compressed and a collection rate of 1/10s, 3 days of data is <100KiB per timeseries, ie 0.5GiB for 10k source timeseries.