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Diffstat (limited to 'users')
| -rw-r--r-- | users/wpcarro/website/blog/posts.nix | 7 | ||||
| -rw-r--r-- | users/wpcarro/website/blog/posts/restic.md | 91 |
2 files changed, 98 insertions, 0 deletions
diff --git a/users/wpcarro/website/blog/posts.nix b/users/wpcarro/website/blog/posts.nix index b9345a5ca141..b791f03654ce 100644 --- a/users/wpcarro/website/blog/posts.nix +++ b/users/wpcarro/website/blog/posts.nix @@ -36,4 +36,11 @@ content = ./posts/csharp-unused-variables.md; draft = false; } + { + key = "restic-field-guide"; + title = "Beginner's Field Guide to restic"; + date = 1656645093; + content = ./posts/restic.md; + draft = false; + } ] diff --git a/users/wpcarro/website/blog/posts/restic.md b/users/wpcarro/website/blog/posts/restic.md new file mode 100644 index 000000000000..4af1fab3682f --- /dev/null +++ b/users/wpcarro/website/blog/posts/restic.md @@ -0,0 +1,91 @@ +Continuing along the trend that [Profpatsch][2] recently inspired in me: writing +short notes to myself instead of fully fledged blog posts aimed at some +unknowable audience. Today we're looking at how I burned myself by only +*partially* RTFD. + +## Background + +I recently started using [restic][4] and NixOS thanks to the help of [TVL's +`restic.nix` module][1]. I setup `1x/h` backups to [MinIO][3] (S3-compatible +storage) for just a handful of `/var/lib` directories (`~9GiB` total), but after +a few days MinIO reported that my bucket size was `O(100GiB)`! + +> What's going on? +> -- me + +```shell +$ restic stats +repository 763bfe37 opened successfully, password is correct +scanning... +Stats in restore-size mode: +Snapshots processed: 175 + Total File Count: 31369384 + Total Size: 21.027 GiB +``` + +> Wait: 20GiB... wat? +> -- me (moments later) + +Maybe we're snapshotting our MinIO buckets, and that's contributing to our +bucket size. Checking the logs proved that `restic` was backing-up `1.5GiB/h`, +which supported MinIO's reports. + +> Ah maybe `restic stats` isn't reporting what I *think* it's reporting... +> -- me (again) + +Let's consult Le Docs: + +```shell +$ restic stats -h + +The "stats" command walks one or multiple snapshots in a repository +and accumulates statistics about the data stored therein. It reports +on the number of unique files and their sizes, according to one of +the counting modes as given by the --mode flag. + +It operates on all snapshots matching the selection criteria or all +snapshots if nothing is specified. The special snapshot ID "latest" +is also supported. Some modes make more sense over +just a single snapshot, while others are useful across all snapshots, +depending on what you are trying to calculate. + +[to be continued] +``` + +This is where I stopped reading (the first time). But then I returned a second +time as I was running low on theories... + +```shell +[continued] + +The modes are: + +* restore-size: (default) Counts the size of the restored files. +* files-by-contents: Counts total size of files, where a file is + considered unique if it has unique contents. +* raw-data: Counts the size of blobs in the repository, regardless of + how many files reference them. +* blobs-per-file: A combination of files-by-contents and raw-data. +``` + +Bingo: `--mode=raw-data` **not** `--mode=restore-size`. + +## Solution + +```shell +$ restic stats --mode=raw-data +repository 763bfe37 opened successfully, password is correct +scanning... +Stats in raw-data mode: +Snapshots processed: 175 + Total Blob Count: 710988 + Total Size: 303.216 GiB +``` + +> Ah... the world agrees again. +> -- me + +[1]: https://cs.tvl.fyi/depot@2ec0d3611960b163a7052e8554ba065f3c89a8cc/-/blob/ops/modules/restic.nix?L9 +[2]: https://github.com/profpatsch +[3]: https://min.io/ +[4]: https://restic.net/ |