Reduce e2e flakiness by changing protocol parameters

[sfauvel]

Content

Change protocol parameters to reduce e2e test flakiness.

We decrease the k parameter of the protocol to 145 to avoid an epoch gap due to a too low number of signatures (less than 150).
This PR also print the last aggregator error in the console to help investigation when tests fail.

Example of the error shown in log when test fail

----------------------------------------------------------------------------------------------------
MITHRIL-AGGREGATOR LOGS - LAST 1 ERROR(S):
----------------------------------------------------------------------------------------------------
10293-{"msg":">> update_epoch_settings","v":0,"name":"mithril-aggregator","level":20,"time":"2025-02-12T11:57:08.013719446+01:00","hostname":"sfauvel-XPS-15-9560","pid":238456,"src":"MithrilEpochService"}
10294-{"msg":"Inserting epoch settings in epoch 37","v":0,"name":"mithril-aggregator","level":20,"time":"2025-02-12T11:57:08.01372586+01:00","hostname":"sfauvel-XPS-15-9560","pid":238456,"src":"MithrilEpochService","epoch_settings":"AggregatorEpochSettings { protocol_parameters: ProtocolParameters { k: 250, m: 210, phi_f: 0.8 }, cardano_transactions_signing_config: CardanoTransactionsSigningConfig { security_parameter: BlockNumber(1), step: BlockNumber(15) } }"}
10295-{"msg":">> precompute_epoch_data","v":0,"name":"mithril-aggregator","level":20,"time":"2025-02-12T11:57:08.017775711+01:00","hostname":"sfauvel-XPS-15-9560","pid":238456,"src":"AggregatorRunner"}
10296-{"msg":">> precompute_epoch_data","v":0,"name":"mithril-aggregator","level":20,"time":"2025-02-12T11:57:08.017797842+01:00","hostname":"sfauvel-XPS-15-9560","pid":238456,"src":"MithrilEpochService"}
10297-{"msg":">> is_certificate_chain_valid","v":0,"name":"mithril-aggregator","level":20,"time":"2025-02-12T11:57:08.033187445+01:00","hostname":"sfauvel-XPS-15-9560","pid":238456,"src":"AggregatorRunner"}
10298:{"msg":"An error occurred, runtime state kept. message = 'certificate chain is invalid'","v":0,"name":"mithril-aggregator","level":50,"time":"2025-02-12T11:57:08.03436876+01:00","hostname":"sfauvel-XPS-15-9560","pid":238456,"src":"AggregatorRuntime","nested_error":"There is an epoch gap between the last certificate epoch (Epoch(31)) and current epoch (Epoch(35))

Stack backtrace:
   0: anyhow::error::<impl core::convert::From<E> for anyhow::Error>::from
   1: <mithril_aggregator::services::certifier::certifier_service::MithrilCertifierService as mithril_aggregator::services::certifier::interface::CertifierService>::verify_certificate_chain::{{closure}}
   2: <mithril_aggregator::services::certifier::buffered_certifier::BufferedCertifierService as mithril_aggregator::services::certifier::interface::CertifierService>::verify_certificate_chain::{{closure}}
   3: <mithril_aggregator::runtime::runner::AggregatorRunner as mithril_aggregator::runtime::runner::AggregatorRunnerTrait>::is_certificate_chain_valid::{{closure}}
   4: mithril_aggregator::runtime::state_machine::AggregatorRuntime::cycle::{{closure}}
   5: mithril_aggregator::commands::serve_command::ServeCommand::execute::{{closure}}::{{closure}}
   6: tokio::runtime::task::core::Core<T,S>::poll
   7: tokio::runtime::task::harness::Harness<T,S>::poll
   8: tokio::runtime::scheduler::multi_thread::worker::Context::run_task
   9: tokio::runtime::scheduler::multi_thread::worker::Context::run
  10: tokio::runtime::context::runtime::enter_runtime
  11: tokio::runtime::scheduler::multi_thread::worker::run
  12: <tokio::runtime::blocking::task::BlockingTask<T> as core::future::future::Future>::poll
  13: tokio::runtime::task::core::Core<T,S>::poll
  14: tokio::runtime::task::harness::Harness<T,S>::poll
  15: tokio::runtime::blocking::pool::Inner::run
  16: std::sys::backtrace::__rust_begin_short_backtrace
  17: core::ops::function::FnOnce::call_once{{vtable.shim}}
  18: std::sys::pal::unix::thread::Thread::new::thread_start
  19: start_thread
             at ./nptl/pthread_create.c:442:8
  20: __GI___clone3
             at ./misc/../sysdeps/unix/sysv/linux/x86_64/clone3.S:81"}

Feb 12 10:57:08.088 INFO Stopping Mithril infrastructure
Feb 12 10:57:08.088 INFO Stopping mithril-signer-1-pool1hu9q6gg7w4s2v52n7kuengae4a7p2ym9rj46juxjqpfa5dh5dm4
Feb 12 10:57:08.095 INFO Stopping mithril-signer-2-pool1gfav880r9mhu5l7t5ymxmd5d0g4vrtj6faszzmgeks847sg87ym
Feb 12 10:57:08.103 INFO Stopping aggregator
Feb 12 10:57:08.114 INFO Stopping the Devnet, script: /tmp/mithril/devnet/stop.sh
>> Stop Cardano network
>> Stop Mithril network
cardano-node: thread killed
cardano-node: thread killed
cardano-node: thread killed
 
----------------------------------------------------------------------------------------------------
Mithril End to End test outcome:
----------------------------------------------------------------------------------------------------
Error(Unretryable): Mithril End to End test failed

Caused by:
    Minimum expected mithril stake distribution epoch not reached : 31 < 32

Pre-submit checklist

• Branch
  • Tests are provided (if possible)
  • Crates versions are updated (if relevant)
  • CHANGELOG file is updated (if relevant)
  • Commit sequence broadly makes sense
  • Key commits have useful messages
• PR
  • No clippy warnings in the CI
  • Self-reviewed the diff
  • Useful pull request description
  • Reviewer requested
• Documentation
  • Update README file (if relevant)
  • Update documentation website (if relevant)
  • Add dev blog post (if relevant)

Issue(s)

Relates to #2222

[github-actions]

Test Results

    4 files  ±0     56 suites  ±0   20m 54s ⏱️ +26s
1 597 tests +1  1 597 ✅ +1  0 💤 ±0  0 ❌ ±0 
1 901 runs  +1  1 901 ✅ +1  0 💤 ±0  0 ❌ ±0 

Results for commit 22ba641. ± Comparison against base commit f9b2d69.

♻️ This comment has been updated with latest results.

[jpraynaud]

LGTM 👍

[Alenar]

LGTM