At a high level, this release contains:

• Performance improvements during ingest and queries
• Add support for saving and retrieving metric metadata information coming from Prometheus
• Improve system observability
• Bug fixes

Performance improvements

This release contains significant improvements for both ingest and queries. During ingest, we improve memory management to reduce pressure on the garbage collector as well as reduce the amount of work that happens when a key is added to a labelset. For queries, we add more efficient fetching of labels, especially in high latency environments, add pushdowns of vector selectors and the rate and increase functions, reduce some pushdown limitations so that more queries can use pushdowns, and improve memory usage.

Observability improvements

• We added better logging of the achieved throughput of Promscale.
• New warnings when the system can't keep up with the ingest load
• Debug level logging of the SQL queries produced by PromQL evaluation.
• Better visibility into maintenance tasks, including a new verbose_logging mode and updates to the application name as the jobs move along.

Bug fixes

• Password masking during logging
• Deadlocks during maintenance tasks

Prom-migrator

This is a beta release for Prom-migrator. It contains a bunch of features that were requested by users, highlights of which includes:

1. The ability to retry migrating a slab in case of a timeout or an error. The behavior of reader and/or writer component on a timeout or error can be controlled by [retry, skip, abort].
2. The ability to set custom timeouts.
3. The ability to increase the time-range of successive slabs being fetched. This can help speed up the migration.
4. Increase the maximum duration of a slab. Non-Prometheus-based storages, which do not have 2 hours limit on blocks, can benefit from this in case of pushing of slabs.
5. Better memory control by adding the option to run the garbage collector after each slab is pushed.
6. Human readable time (RFC3339) for start or end of migration.

Other than these, the release also contains performance improvements related to memory usage.

Breaking CLI changes in prom-migrator

• -mint is now renamed to -start
• -maxt is now renamed to -end
• -concurrent-pulls is now renamed to -concurrent-pull
• -read-url is now renamed to -reader-url
• -write-url is now renamed to -writer-url

For more usage/CLI flags details, please see the README.md.

Changelog

e5791cd Add debian packaging to goreleaser
91d90b8 Add debugging data in metrics and logs, refactor throughput watcher.
c39ea1d Add ewma package for rate calculation.
6a10e63 Add integration-tests to verify retrying behaviour on error.
4d26951 Add optional logging for maintenance jobs
07c815d Add support for promscale ext 0.2.x
7bcb492 Add tests for metadata ingestion/querying.
8838af6 Add warning if jobs take too long
1a78024 Adds support for TimescaleDB nighty smoke tests.
ccdc0b1 Adds support for metric-metadata in Promscale.
0aa7f12 Allow auto_explain to be turned on in maintenance jobs
2fe9ab3 Allow pushdown of multiple clauses in a single query
af9cddd Buffer allocation pool for parsing protobuf
1219879 Bunch up view creation
e3e5084 Docs for multi-tenancy.
29a04f8 Finishing refinements for metric-metadata.
ebe7ad8 Fix DB URI issues for URIs with missing ? parameter settings separator
89df3c2 Fix bad check for error in MetricTableName
9f8a5eb Fix label fetching during querying
461312a Fix possible deadlock in delete_expired_series().
c52aa84 Fix typo of README.md
c3d10f5 Implement APIs for metadata support.
66adb11 Improve delete_expired_series
b52954f Log time consumed by SQL queries in debug level & drop HA debug logs noise
1dd2b93 Make prom-migrator runtime more customizable.
aca638f Optimize SQL for pushdowns
189f275 Prepare for 0.5.0 release
6dc3fb1 Prepare for the next development cycle
e2e0d6c Pushdown rate and increase optimizations
081ecb7 Recovery actions and refactoring in prom-migrator.
23360f4 Refactor pushdowns
dd8b1ed Set application_name in maintenance jobs
4bbb867 Stop fetching timestamps for regular series from the DB
1fc1a8e Support for warning user on slow data ingestion.
13e6825 Support vector selector pushhdown
9e4f128 Test fixes
dd46a90 Test fixes
4bab710 Update PromQL with upstream upto May 11.
4483827 Update Prompb with upstream upto May 7.
bc4846c Update docs in prom-migrator.
3217a93 Upgrade to pre-release versions in tests
e59a363 Use more reliable methods of password masking
87b7f2b Use pools for pgx scan objects
cc49108 add fgprof support
41c4ad7 add static deploy.yaml that includes Kubernetes manifests for Promscale
f50c9be filter out indent characters from SQL query log
5c5eb73 move querier methods to NewQuerierPgxConn(), so that these methods will be only invoked for querying calls.
135f3e2 nits + comments + test fixes
9d18464 review iteration 2
ad00081 typo error in spelling

Docker images

• docker pull timescale/promscale:0.5.0
• docker pull timescale/promscale:0.5
• docker pull timescale/promscale:latest