Need to improve multi-core processing

[UMU618]

Run top -H -p <PID of nodeos>, we see the main thread is too busy, while the others are low cost.

EOS CPU Usage is always 100% which only use one cpu core. #8476

[heifner]

Can you point to any reference information on this?

[jgiszczak]

Post always queues, maximizing the possibility for thread utilization. The load imbalance among threads in nodeos is not related to the use of post().

[UMU618]

@jgiszczak I think the problem is in net_plugin:

https://github.com/EOSIO/eos/blob/880c9c4186911d0faa3dcf64cdaab8042a7a0188/plugins/net_plugin/net_plugin.cpp#L176-L179

strand + post make tasks executed in main thread.

[UMU618]

These functions are in deep call stack:

• fc::sha256::encoder::write(char const*, unsigned int)

• eosio::connection::queue_write(std::__1::shared_ptr<std::__1::vector<char, std::__1::allocator<char> > > const&, bool, int, std::__1::function<void (boost::system::error_code, unsigned long)>, bool)

• eosio::dispatch_manager::bcast_transaction(std::__1::shared_ptr<eosio::chain::transaction_metadata> const&)

• eosio::chain::signed_block::~signed_block()

• boost::signals2::detail::slot_call_iterator_t<boost::signals2::detail::variadic_slot_invoker<boost::signals2::detail::void_type, std::__1::tuple<std::__1::shared_ptr<eosio::chain::transaction_trace> const&, eosio::chain::signed_transaction const&> >, std::__1::__list_iterator<boost::shared_ptr<boost::signals2::detail::connection_body<std::__1::pair<boost::signals2::detail::slot_meta_group, boost::optional<int> >, boost::signals2::slot<void (std::__1::tuple<std::__1::shared_ptr<eosio::chain::transaction_trace> const&, eosio::chain::signed_transaction const&>), boost::function<void (std::__1::tuple<std::__1::shared_ptr<eosio::chain::transaction_trace> const&, eosio::chain::signed_transaction const&>)> >, boost::signals2::mutex> >, void*>, boost::signals2::detail::connection_body<std::__1::pair<boost::signals2::detail::slot_meta_group, boost::optional<int> >, boost::signals2::slot<void (std::__1::tuple<std::__1::shared_ptr<eosio::chain::transaction_trace> const&, eosio::chain::signed_transaction const&>), boost::function<void (std::__1::tuple<std::__1::shared_ptr<eosio::chain::transaction_trace> const&, eosio::chain::signed_transaction const&>)> >, boost::signals2::mutex> >::dereference() const

https://github.com/EOSIO/eos/blob/880c9c4186911d0faa3dcf64cdaab8042a7a0188/plugins/net_plugin/net_plugin.cpp#L1099-L1101