Canton 2.9.3

Canton 2.9.3 has been released on July 22, 2024. You can download the Daml Open Source edition from the Daml Connect Github Release Section. The Enterprise edition is available on Artifactory. Please also consult the full documentation of this release.

Summary

This is a maintenance release of Canton that fixes one high risk bug, which can crash a participant node due to out of memory, and two low risk bugs.

Bugfixes

(24-017, High): Participants crash with an OutOfMemoryError

Description

The TaskScheduler keeps a huge number of tasks into a queue. The queue has been newly introduced. Therefore the memory comsumption (HEAP) is much higher than in previous versions. The queue size is proportional to the number of requests processed during the decision time.

Affected Deployments

Participant

Impact

Memory consumption is much higher than in previous Canton versions.

Symptom

The participant crashes with an OutOfMemoryError.

Workaround

Test the participant under load, increase the heap size accordingly. If possible, decrease confirmation response timeout and mediator reaction timeout.

Likeliness

High likelihood under high load and with large confirmation response and mediator reaction timeouts.

Recommendation

Upgrade to 2.9.3.

(24-018, Low): Participants log "ERROR: The check for missing ticks has failed unexpectedly"

Description

The TaskScheduler monitoring crashes and logs an Error.

Affected Deployments

Participant

Impact

The monitoring of the task scheduler crashes.

Symptom

You see an error in the logs: ERROR: The check for missing ticks has failed unexpectedly..

Workaround

If you need the monitoring to trouble-shoot missing ticks, restart the participant to restart the monitoring.

Likeliness

This will eventually occur on every system.

Recommendation

Ignore the message until upgrading to 2.9.3.

(24-015, Low): Pointwise flat transaction Ledger API queries can unexpectedly return TRANSACTION_NOT_FOUND

Description

When a party submits a command that has no events for contracts whose stakeholders are amongst the submitters, the resulted transaction cannot be queried by pointwise flat transaction Ledger API queries. This impacts GetTransactionById, GetTransactionByEventId and SubmitAndWaitForTransaction gRPC endpoints.

Affected Deployments

Participant

Impact

User might perceive that a command was not successful even if it was.

Symptom

TRANSACTION_NOT_FOUND is returned on a query that is expected to succeed.

Workaround

Query instead the transaction tree by transaction-id to get the transaction details.

Likeliness

Lower likelihood as commands usually have events whose contracts' stakeholders are amongst the submitting parties.

Recommendation

Users are advised to upgrade to the next patch release during their maintenance window.

Compatibility

The following Canton protocol and Ethereum sequencer contract versions are supported:

Dependency	Version
Canton protocol versions	5, 6*

Canton has been tested against the following versions of its dependencies:

Dependency	Version
Java Runtime	OpenJDK 64-Bit Server VM Zulu11.72+19-CA (build 11.0.23+9-LTS, mixed mode)
Postgres	Recommended: PostgreSQL 12.19 (Debian 12.19-1.pgdg120+1) – Also tested: PostgreSQL 11.16 (Debian 11.16-1.pgdg90+1), PostgreSQL 13.15 (Debian 13.15-1.pgdg120+1), PostgreSQL 14.12 (Debian 14.12-1.pgdg120+1), PostgreSQL 15.7 (Debian 15.7-1.pgdg120+1)
Oracle	19.20.0