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**Related issue:** Resolves#45715
# Details
This PR refactors the way the charts module stores historical data to
use the [roaring bitmap](https://github.com/RoaringBitmap/roaring)
package instead of saving raw bitmaps. See [this
blurb](https://github.com/RoaringBitmap/roaring#how-does-roaring-compares-with-the-alternatives)
to learn how roaring compresses data, but TL;DR for our purposes it
represents a huge improvement especially for larger deployments where
host ID numbers may be very large. In testing, some data was reduced
96%.
The majority of the changes in this PR are straight swapping of types
from `[]byte` to `*roaring.Bitmap` in vars and function signatures, and
updating the internals of our bit math helpers to use roaring methods
instead of native AND and OR methods. I've tried to comment on all
functional changes.
Since the charts have been shipped already, so there will be data in the
wild in the prior "dense" format, the code still handles dense bitmaps
on _read_, but will always _write_ roaring bitmaps. The majority of the
data will therefore have turned over within 30 days on its own, but I
plan on a follow-up PR that will transform open rows when the cron runs
so that we should be guaranteed to turn over completely within 30 days.
# Checklist for submitter
If some of the following don't apply, delete the relevant line.
- [X] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
See [Changes
files](https://github.com/fleetdm/fleet/blob/main/docs/Contributing/guides/committing-changes.md#changes-files)
for more information.
- [X] Input data is properly validated, `SELECT *` is avoided, SQL
injection is prevented (using placeholders for values in statements), JS
inline code is prevented especially for url redirects, and untrusted
data interpolated into shell scripts/commands is validated against shell
metacharacters.
## Testing
- [X] Added/updated automated tests
- Tests updated to accommodate the new format, and existing unchanged
tests act as proof against regression
- [X] QA'd all new/changed functionality manually
- Using a tool that dumps the `host_scd_data` rows data into a JSON file
(with the keys being entity_id+data and the values being host IDs on
that date), compared the data from main branch and this and confirmed
they're identical
- With a host count of ~9000, some of which have IDs of over 1,000,000,
the data storage requirements were:
* 82,558,976 bytes for dense
* 2,867,200 for roaring (a 96% decrease)
For unreleased bug fixes in a release candidate, one of:
- [X] Confirmed that the fix is not expected to adversely impact load
test results
- should hugely improve
- [X] Alerted the release DRI if additional load testing is needed
## Database migrations
- [X] Checked schema for all modified table for columns that will
auto-update timestamps during migration.
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **New Features**
* Implemented roaring bitmaps in historical data collection to optimize
bitmap handling for chart data aggregation
* Added encoding support to bitmap storage schema for flexible data
representation
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Scott Gress
d7fa35e417