Slow import of Cardano transactions in `testing-mainnet`

[jpraynaud]

Why

We have noticed very slow import of the Cardano transactions on the testing-mainnet network (more than 2 weeks for the aggregator database).

Important

After investigation, it appears that the hard disk that is used on the aggregator is not fast enough and should be upgraded.
We have tested faster disk on the VM and this has fixed the problem. We have not seen the problem occurring on the signers side as their database is pruned along the way: this means that only the aggregator needs to be upgraded.

What

Investigate the origin of the problem and implement a fix.

How

• Investigate the problem
• Upgrade the data disk of the testing-mainnet VM to pd-balanced
  • check no SSL problem => it will require a regeneration of the SSL certificate
  • check disk backup policy is activated
• Re-import aggregator Cardano transactions and check that it takes reasonable time
• Prepare the upgrade of the data disk of the release-mainnet VM to pd-balanced and plan it with a release prior to activation of the certification of Cardano transactions

Later

• Create a runbook for upgrading the disk instance of a VM