Querying a single value in Hyperledger Fabric is taking 10-20sec - hyperledger-fabric

Question

I have just built a Hyperledger Fabric 1.4.4 network on 2 org / nodes / orderers using with Raft https://github.com/Altoros/Ansible-Fabric-Starter
The network is working great, but when I try to select a single value from my custom chaincode, query takes 10-20 secs, quite a lot. I'm using LevelDB.
It is hosted on 2 x t3a-small instances on AWS ( 2vCPU, 2GB Ram )
When it comes to writing a data, it is not so long (258 ms) which is acceptable.
How should I improve the read latency ? Is it just a matter of infrastructure ( vertical scaling for my VMs) or did I forget a configuration ?

Answer 1

At ansible-fabric-starter that you delivered, it seems that the chaincode query function is called through the peer chaincode invoke command.
test_bilateral.yml
...
raw: "docker exec cli.{{ org }}.{{ global_domain }} bash -c 'peer chaincode invoke --cafile /etc/hyperledger/artifacts/crypto-config/ordererOrganizations/{{ global_domain }}/tlsca/tlsca.{{ global_domain }}-cert.pem --tls -o orderer{{ orderer_id | default(0) }}.{{ global_domain }}:7050 -C {{ invoke_channel_name }} -n {{ chaincode_name }} -c {{ chaincode_update_json | to_json }}'"
...
test.yml
...
raw: "docker exec cli.{{ org }}.{{ global_domain }} bash -c 'peer chaincode invoke --cafile /etc/hyperledger/artifacts/crypto-config/ordererOrganizations/{{ global_domain }}/tlsca/tlsca.{{ global_domain }}-cert.pem --tls -o orderer{{ orderer_id | default() }}.{{ global_domain }}:7050 -C {{ invoke_channel_name }} -n {{ chaincode_name }} -c {{ chaincode_update_json | to_json }}'"
...
In other words, when you see the transaction flow, it is inferred that your query command searches the ledger, sends the result to the orderer, and includes all the latency until the blockchain is updated.
peer chaincode invoke includes the process of reflecting the endorsement of the transaction proposal to the ledger (ordering/block packaing/validationCheck(with mvcc)/eventEmit...).
The query in the chaincode is simply a function in ansible-fabric-starter and should not be confused with the peer chaincode query on the fabric network. Try to run it based on the peer chaincode query command.
here's an additional example to help you understand.
peer chaincode invoke '{"Args":["invoke","a","100"]}'
# stdout : a = 100
# fabric : a = 100, [blockchain]: added block;
peer chaincode query '{"Args":["invoke","a","300"]}'
# stdout : a = 300
# fabric : a = 100
# something... like simulation
peer chaincode invoke '{"Args":["query","a"]}' # this is your situation
# stdout : a = 100
# fabric : a = 100, [blockchain]: added block;
peer chaincode query'{"Args":["query","a"]}' # change like this
# stdout : a = 100
# fabric : a = 100