This may be a breaking change for users who rely on particular kopia metrics (unlikely):
- introduced blob-level metrics:
* `kopia_blob_download_full_blob_bytes_total`
* `kopia_blob_download_partial_blob_bytes_total`
* `kopia_blob_upload_bytes_total`
* `kopia_blob_storage_latency_ms` - per-method latency distribution
* `kopia_blob_errors_total` - per-method error counter
- updated cache metrics to indicate particular cache
* `kopia_cache_hit_bytes_total{cache="CACHE_TYPE"}`
* `kopia_cache_hit_total{cache="CACHE_TYPE"}`
* `kopia_cache_malformed_total{cache="CACHE_TYPE"}`
* `kopia_cache_miss_total{cache="CACHE_TYPE"}`
* `kopia_cache_miss_errors_total{cache="CACHE_TYPE"}`
* `kopia_cache_miss_bytes_total{cache="CACHE_TYPE"}`
* `kopia_cache_store_errors_total{cache="CACHE_TYPE"}`
where `CACHE_TYPE` is one of `contents`, `metadata` or `index-blobs`
- reorganized and unified content-level metrics:
* `kopia_content_write_bytes_total`
* `kopia_content_write_duration_nanos_total`
* `kopia_content_compression_attempted_bytes_total`
* `kopia_content_compression_attempted_duration_nanos_total`
* `kopia_content_compression_savings_bytes_total`
* `kopia_content_compressible_bytes_total`
* `kopia_content_non_compressible_bytes_total`
* `kopia_content_after_compression_bytes_total`
* `kopia_content_decompressed_bytes_total`
* `kopia_content_decompressed_duration_nanos_total`
* `kopia_content_encrypted_bytes_total`
* `kopia_content_encrypted_duration_nanos_total`
* `kopia_content_hashed_bytes_total`
* `kopia_content_hashed_duration_nanos_total`
* `kopia_content_deduplicated_bytes_total`
* `kopia_content_read_bytes_total`
* `kopia_content_read_duration_nanos_total`
* `kopia_content_decrypted_bytes_total`
* `kopia_content_decrypted_duration_nanos_total`
* `kopia_content_uploaded_bytes_total`
Also introduced `internal/metrics` framework which constructs Prometheus metrics in a uniform way and will allow us to include some of these metrics in telemetry report in future PRs.
From https://github.com/google/gvisor/tree/master/tools/checklocks
This will perform static verification that we're using
`sync.Mutex`, `sync.RWMutex` and `atomic` correctly to guard access
to certain fields.
This was mostly just a matter of adding annotations to indicate which
fields are guarded by which mutex.
In a handful of places the code had to be refactored to allow static
analyzer to do its job better or to not be confused by some
constructs.
In one place this actually uncovered a bug where a function was not
releasing a lock properly in an error case.
The check is part of `make lint` but can also be invoked by
`make check-locks`.
* feat(repository): ensure we don't run parallel fetches for the same blob IDs
Fixed a bunch of test flakes.
* fixed race condition, limit the size of mutex cache by using LRU
