The content compiled this time is the Q&A in the community from June to July for more developers’ reference (some high-quality questions in the community are not coherent enough to be included, please click the menu bar of the official account to join the community to communicate together). There are more questions and answers in the community issue, which are described in more detail. Developers can search according to keywords before asking questions. Developers are welcome to submit issues according to the Q&A template, and developers who are willing to participate in the community issue board maintenance are also welcome.
Issue question and answer collection link:
https://git.chainmaker.org.cn/chainmaker/issue/-/issues?scope=all&utf8=%E2%9C%93&state=all
Featured Community Q&A
installation configuration
1. Q: Excuse me, what do monitor and pprof in the node configuration file chainmaker.yml mean?
A: Whether monitor starts promomethus monitoring data collection; whether pprof starts go pprof performance collection data.
2. Q: I have a question. If you use tikv, I think only port 2379 is configured. Can it be understood as: (1) Each node corresponds to a tidb cluster? (2) Don't 4 chain nodes correspond to a tidb cluster?
A: (1) Yes;
(2) It is possible, but it is not recommended to do so. You can configure dbprefix to allow multiple nodes to share a tikv.
3. Q: Changan Chain’s block cutting strategy, block data size is limited in that process.
A: At present, it is supported to control the number of transactions in the block and the block interval through the chain configuration (essentially, the interval between trying to pack the block), and does not support precise control based on the size of the block data, because the transaction has not been executed when the block is proposed, and the tx cannot be predicted .result size.
Q: The block_size setting in the bc.yml file is useless, right?
A: Yes.
4. Q: Can the solidity contract code be deployed directly in ChainMaker SmartEditor? Are there any tutorials or documentation?
A: smarteditor only supports go contracts.
5. Q: Does Changan Chain have advanced deployment documents? Consensus nodes and commmon nodes need to be deployed separately.
A: Refer to the multi-machine deployment document.
6. Q: I have a question I want to know. If you plan to use the Changan Chain to build a chain, will there be a limit to the number of nodes?
A: At present, the Changan chain supports consensus nodes of more than 100 levels and synchronization nodes of more than 10,000 levels. It is sufficient for normal business.
transaction related
7. Q: CMC queries the chain configuration and reports an error that the transaction pool has stopped. What is the matter?
A: When the chain restarts, it will load the transactions dumped during the previous shutdown by default, and you need to wait for all modules to start before sending transactions.
8. Q: Can Changan Chain monitor the transaction pool?
A: Provides an interface for querying the number of transaction pools. Changan chain transaction pools are packaged on the chain according to the first-in-first-out principle, so currently only three-level query functions are provided: including the overall status of the transaction pool, the list of transaction IDs in queue and pending, Query the three interfaces of transactions in the transaction pool according to the transaction ID.
9. Q: Why does this happen in the reading result of bytes32 data?
A: You can analyze it yourself. The cmc tool does not recognize it.
Certificate related
10. Q: Does our Changan chain certificate mode currently support national secret cipher machines?
A: Support.
11. Q: I would like to ask a basic question, the chain certificate in the alliance chain usually uses a self-signed certificate or a certificate issued by a CA institution?
A: If it is for your own use, a self-signed certificate is fine. If it is for commercial use, it is recommended to find a CA to issue it, depending on the importance.
12. Q: When initializing the browser configuration of the single-machine 4-node Changan chain, the organization certificate, user certificate and user private key were exported in strict accordance with the requirements of the technical documentation, but when imported, the prompt "subscription chain failed, please check your Is the information filled in correct and try again", what is wrong?
A: If there is no problem with all configurations, restart all nodes, and then re-import the file and it will be successful.
13. Q: Does the certificate generated by the Changan chain cryptogen tool support the ed25519 algorithm? I don’t seem to see it.
A: There is no Ed25519.
Q: Isn't 25519 better than ecdsa?
A: It will be considered later. However, compared to Ed25519, SM2 is recommended. Chang'an Chain supports complete national secret certificates and national secret TLS standards!
Q: Is it possible to configure a designated national secret library? The performance of Tongji is too low.
A: Yes. There are three national secret vaults to choose from. Configured in .chainmaker.yml.
Consensus related
14. Q: Which of the consensus algorithms Maxbft and Tbft has better performance?
A: MaxBFT is used when the number of nodes is large, and TBFT is used in other cases;
Q: Is there any supported cft consensus?
A: Raft consensus is supported.
15. Q: For the maxbft and pow consensus algorithms on the Changan Chain, when the block generation time comes and no transactions are generated, should an empty block be generated directly?
A: PoW is not supported. Empty blocks are required in the current version, and will not be released after versions 2.3.2 and 300.
other problems
16. Q: Does opening the monitor on the chain have a big impact on performance?
A: The actual measurement has little impact.