Why does my POA network generate block so slowly

[RustMan88]

Before filing a new issue, please provide the following information.

• Parity Ethereum version: v2.1.10
• Operating system: Linux
• Installation: built from source
• Fully synchronized: yes
• Network: private
• Restarted: no

Your issue description goes here below. Try to include actual vs. expected behavior and steps to reproduce the issue.

my demo-spec.json:

{
    "name": "DemoPoA",
    "engine": {
        "authorityRound": {
            "params": {
                "stepDuration": "4",
                "blockReward": "0x4563918244F40000",
                "validators": {
                    "multi":{
                       "0":{ "list": ["0x4e7eaf9f3bfa7fe3fd3c96730f4b82aff883d3bf", "0x2dcbfced9ec8e2d1cbf5ee76092cdce4798ec550","0x3b9b09b6c13c804b450869d8ee695a157fb9c4c6"]}
                    }
                }
            }
        }
    },
    "params": {
        "gasLimitBoundDivisor": "0x0400",
        "maximumExtraDataSize": "0x20",
        "minGasLimit": "0x1388",
        "networkID": "0x232323"
    },
    "genesis": {
        "seal": {
            "authorityRound": {
                "step": "0x0",
                "signature": "0x0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"
            }
        },
        "difficulty": "0x20000",
        "gasLimit": "0x5B8D80"
    },
    "accounts": {
        "0x0000000000000000000000000000000000000001": {
            "balance": "1",
            "builtin": {
                "name": "ecrecover",
                "pricing": {
                    "linear": {
                        "base": 3000,
                        "word": 0
                    }
                }
            }
        },
        "0x0000000000000000000000000000000000000002": {
            "balance": "1",
            "builtin": {
                "name": "sha256",
                "pricing": {
                    "linear": {
                        "base": 60,
                        "word": 12
                    }
                }
            }
        },
        "0x0000000000000000000000000000000000000003": {
            "balance": "1",
            "builtin": {
                "name": "ripemd160",
                "pricing": {
                    "linear": {
                        "base": 600,
                        "word": 120
                    }
                }
            }
        },
        "0x1d5d69cc9f2b381ce2d27da3a076900f2770fbe7": {
            "balance": "100000000000000000000000"
        },
        "0x0000000000000000000000000000000000000004": {
            "balance": "1",
            "builtin": {
                "name": "identity",
                "pricing": {
                    "linear": {
                        "base": 15,
                        "word": 3
                    }
                }
            }
        }
    }
}

my node.toml:

[parity]
chain = "/home/ubuntu/DFChain/deploy/aura/demo-spec.json"
base_path = "/home/ubuntu/DFChain/deploy/aura/node1/parity"

[network]
port = 30301

[rpc]
port = 8541
apis = ["web3", "eth", "net", "personal", "parity", "parity_set", "traces", "rpc", "parity_accounts"]

[websockets]
port = 8451

[account]
password = ["/home/ubuntu/DFChain/deploy/aura/node1/node.pwds"]

[mining]
engine_signer = "0x2dcbfced9ec8e2d1cbf5ee76092cdce4798ec550"
reseal_on_txs = "none"

and node0 node1 node2 use a similar configuration, but generate block very slow ,like:

2018-12-18 08:06:16 UTC Imported #498 0xdcb8…9a3e (0 txs, 0.00 Mgas, 0 ms, 0.57 KiB)
2018-12-18 08:06:25 UTC    6/25 peers    302 KiB chain  634 KiB db  0 bytes queue   38 KiB sync  RPC:  0 conn,    0 req/s,    0 µs
2018-12-18 08:06:55 UTC    6/25 peers    302 KiB chain  634 KiB db  0 bytes queue   38 KiB sync  RPC:  0 conn,    0 req/s,    0 µs
2018-12-18 08:06:56 UTC Imported #499 0xd3c5…839b (0 txs, 0.00 Mgas, 0 ms, 0.57 KiB)
2018-12-18 08:07:12 UTC Imported #500 0x0c48…2514 (0 txs, 0.00 Mgas, 0 ms, 0.57 KiB)
2018-12-18 08:07:25 UTC    6/25 peers    302 KiB chain  635 KiB db  0 bytes queue   38 KiB sync  RPC:  0 conn,    0 req/s,    0 µs
2018-12-18 08:07:55 UTC    6/25 peers    302 KiB chain  635 KiB db  0 bytes queue   38 KiB sync  RPC:  0 conn,    0 req/s,    0 µs
2018-12-18 08:08:16 UTC Imported #501 0x858f…dd7d (0 txs, 0.00 Mgas, 0 ms, 0.57 KiB)
2018-12-18 08:08:25 UTC    6/25 peers    302 KiB chain  635 KiB db  0 bytes queue   38 KiB sync  RPC:  0 conn,    0 req/s,    0 µs
2018-12-18 08:08:55 UTC    6/25 peers    302 KiB chain  635 KiB db  0 bytes queue   38 KiB sync  RPC:  0 conn,    0 req/s,    0 µs
2018-12-18 08:08:56 UTC Imported #502 0xd652…dc5c (0 txs, 0.00 Mgas, 0 ms, 0.57 KiB)

why ? i need help ,thanks.

[jam10o-new]

Just to make sure, all of your nodes are online, have the correct engine_signer set, and you see the same blockhashes in their logs for the same blocknumbers?

[RustMan88]

Just to make sure, all of your nodes are online, have the correct engine_signer set, and you see the same blockhashes in their logs for the same blocknumbers?
my nodes are online in same computer,and i sure that the same blockhashes in their logs for the same blocknumbers. like:

[jam10o-new]

Can you run with -l engine or add

[misc]
logging = "engine"

to your node configs and share the additional logs you see?

[ddorgan]

@viking2015 are there actual transactions pending? If not it will take a long time to produce a block. You can include --force-sealing to enable consistent block creation.

[5chdn]

--force-sealing is the correct answer here. 🥇