This would sometimes result in exceptions being thrown if a call was
made in the middle of a schema change.

It's too restrictive and is only useful in a single case of
PersistInstance, which is going to be replaced with OpDml anyway.

This will be changed in a second

To run the test you need xk6 installed
(https://github.com/tarantool/xk6-tarantool).

Georgy Moshkin authored 1 year ago and Yaroslav Dynnikov committed 1 year ago

This used to cause flakyness of test_bucket_rebalancing_respects_replication_factor
like this:

- governor proposes entry at index N with weight updates,
  and waits till it's applied

- commit index is not updated yet, but governor calls rpc::sharding to
  update the weights in the vshard subsystem on instances and passes the
  lagging commit index for syncing

- peers sync up to the lagging commit index and then reconfigure vshard
  to the outdated weights

- governor thinks everything is in order and waits for updates

- the test fails because buckets don't get rebalanced to the storages
  with weights set to 0

Now it is possible to make the second argument (query parameters)
optional. I.e. now we support 'pico.sql([[select * from t]])' as
well as 'pico.sql([[select * from t where a = ?]], {1})'.

Egor Ivkov authored 1 year ago and Егор Ивков committed 1 year ago

They should cover all the cases specified in the CaS Design Document