[Bug]: simdv2 responds error: version 15 does not exist on tx send

[kocubinski]

Is there an existing issue for this?

• I have searched the existing issues

What happened?

When running load tests for benchmarks simapp/v2 responds curiously with:

error in json rpc client, with http response metadata: (Status: 500 Internal Server Error, Protocol HTTP/1.1). RPC error -32603 - Internal error: CheckTx request for tx 2B8A868E87E87B6D6C16F5E4545D87120346FB910E2D58C97340B2E5E2CD33F8 failed: version 7 does not exist

Sometimes the HTTP response code is 200 but with the same error.

error in json rpc client, with http response metadata: (Status: 200 OK, Protocol HTTP/1.1). RPC error -32603 - Internal error: version 25 does not exist

This could indicate a synchronization problem around committing a block.

Cosmos SDK Version

main @ ffa74d1

How to reproduce?

To reproduce checkout 0b74dbe, which is on kocu/x-benchmark. Start up simapp, then the load test and wait a few seconds.

git checkout 0b74dbeeef3f651c28ebc06f03eafcb0ecde68aa
COSMOS_BUILD_OPTIONS=v2 make install && make init-simapp-v2 && simdv2 start
# wait for genesis to complete, could be a few seconds
simdv2 tx benchmark load-test alice --yes

[GNaD13]

As far as I can see, there is a delay between the update of the s.lastCommitInfo value and the actual SC store update. This means that if a TX is sent during this delay, when the StateLatest() function is called in ValidateTx(), there may has an error because the SC store has not been committed in sync with the newly updated version information in lastCommitInfo. This may be the cause of the above error. So to deal with this problem I think we have 2 options:

• We could change something like update s.lastCommitInfo after SC store is completely commited
• Always get lastCommitInfo from SC Lastest Version instead of use both s.lastCommitInfo and SCLatestVersion

I've tested with options 2 and it was running stable, no more same error