EXECUTION_LIMIT_REACHED occurred when a "view" function is called.

[byron1st]

Discord user ID

byron1st

Describe your question in detail.

Hello! I'm running a private blockchain network including 8 validators (Version 1.16.3).
On this blockchain, one of my view functions responded an EXECUTION_LIMIT_REACHED error.
It is weird because, according to the discussion at Discord, EXECUTION_LIMIT_REACHED is related to the usage of gas, but this is a view function, not an entry function.

The fact that this error occurred at a view function is definitely true because, according to the stacktrace, this error occurred at the execute_view_function_in_vm function of Aptos Core. (I attached the stacktrace of this error at the last of this post)

According to the stacktrace, the error occurred during calling a native function of table module, and my view function calls table::contains and table::borrow.
I don't know what the last 12 means from the below stacktrace, so I'm not sure which function is the root of this error.
(Some(ModuleId { address: 63f12417df0177fe3106b899bdd2891112c6ab25b08c4c285ab5d36ee3cd14af, name: Identifier("devices") }), FunctionDefinitionIndex(6), 12),

This view function is quite heavy and this function traverse many elements of Table. So I'm wondering if there is a limit to call some native functions (such as table::contains or table::borrow).

If you need more information, please let me know. I will provide as many as possible.
I want to know the reason of this error, so want to fix it.

Thanks!!

VMError { 
    major_status: EXECUTION_LIMIT_REACHED, 
    sub_status: None, 
    message: Some("Backtrace: Backtrace [
        { fn: "move_binary_format::errors::PartialVMError::finish", file: "/aptos/third_party/move/move-binary-format/src/errors.rs", line: 389 },
        { fn: "move_vm_runtime::interpreter::Interpreter::call_native::{{closure}}", file: "/aptos/third_party/move/move-vm/runtime/src/interpreter.rs", line: 454 },
        { fn: "core::result::Result<T,E>::map_err", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/core/src/result.rs", line: 829 },
        { fn: "move_vm_runtime::interpreter::Interpreter::call_native", file: "/aptos/third_party/move/move-vm/runtime/src/interpreter.rs", line: 447 },
        { fn: "move_vm_runtime::interpreter::Interpreter::execute_main", file: "/aptos/third_party/move/move-vm/runtime/src/interpreter.rs", line: 273 },
        { fn: "move_vm_runtime::interpreter::Interpreter::entrypoint", file: "/aptos/third_party/move/move-vm/runtime/src/interpreter.rs", line: 98 },
        { fn: "move_vm_runtime::runtime::VMRuntime::execute_function_impl", file: "/aptos/third_party/move/move-vm/runtime/src/runtime.rs", line: 395 },
        { fn: "move_vm_runtime::runtime::VMRuntime::execute_function_instantiation", file: "/aptos/third_party/move/move-vm/runtime/src/runtime.rs", line: 441 },
        { fn: "move_vm_runtime::session::Session::execute_function_bypass_visibility", file: "/aptos/third_party/move/move-vm/runtime/src/session.rs", line: 108 },
        { fn: "aptos_vm::aptos_vm::AptosVM::execute_view_function_in_vm", file: "/aptos/aptos-move/aptos-vm/src/aptos_vm.rs", line: 2221 },
        { fn: "aptos_vm::aptos_vm::AptosVM::execute_view_function", file: "/aptos/aptos-move/aptos-vm/src/aptos_vm.rs", line: 2176 },
        { fn: "aptos_api::view_function::view_request", file: "/aptos/api/src/view_function.rs", line: 135 },
        { fn: "aptos_api::view_function::ViewFunctionApi::view_function::{{closure}}::{{closure}}", file: "/aptos/api/src/view_function.rs", line: 71 },
        { fn: "<tokio::runtime::blocking::task::BlockingTask<T> as core::future::future::Future>::poll", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/runtime/blocking/task.rs", line: 42 },
        { fn: "tokio::runtime::task::core::Core<T,S>::poll::{{closure}}", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/runtime/task/core.rs", line: 328 },
        { fn: "tokio::loom::std::unsafe_cell::UnsafeCell<T>::with_mut", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/loom/std/unsafe_cell.rs", line: 16 },
        { fn: "tokio::runtime::task::core::Core<T,S>::poll", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/runtime/task/core.rs", line: 317 },
        { fn: "tokio::runtime::task::harness::poll_future::{{closure}}", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/runtime/task/harness.rs", line: 485 },
        { fn: "<core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/core/src/panic/unwind_safe.rs", line: 272 },
        { fn: "std::panicking::try::do_call", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/panicking.rs", line: 552 },
        { fn: "std::panicking::try", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/panicking.rs", line: 516 },
        { fn: "std::panic::catch_unwind", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/panic.rs", line: 146 },
        { fn: "tokio::runtime::task::harness::poll_future", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/runtime/task/harness.rs", line: 473 },
        { fn: "tokio::runtime::task::harness::Harness<T,S>::poll_inner", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/runtime/task/harness.rs", line: 208 },
        { fn: "tokio::runtime::task::harness::Harness<T,S>::poll", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/runtime/task/harness.rs", line: 153 },
        { fn: "tokio::runtime::task::raw::RawTask::poll", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/runtime/task/raw.rs", line: 201 },
        { fn: "tokio::runtime::task::UnownedTask<S>::run", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/runtime/task/mod.rs", line: 453 },
        { fn: "tokio::runtime::blocking::pool::Task::run", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/runtime/blocking/pool.rs", line: 159 },
        { fn: "tokio::runtime::blocking::pool::Inner::run", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/runtime/blocking/pool.rs", line: 513 },
        { fn: "tokio::runtime::blocking::pool::Spawner::spawn_thread::{{closure}}", file: "/usr/local/cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.35.1/src/runtime/blocking/pool.rs", line: 471 },
        { fn: "std::sys_common::backtrace::__rust_begin_short_backtrace", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/sys_common/backtrace.rs", line: 155 },
        { fn: "std::thread::Builder::spawn_unchecked_::{{closure}}::{{closure}}", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/thread/mod.rs", line: 528 },
        { fn: "<core::panic::unwind_safe::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/core/src/panic/unwind_safe.rs", line: 272 },
        { fn: "std::panicking::try::do_call", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/panicking.rs", line: 552 },
        { fn: "std::panicking::try", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/panicking.rs", line: 516 },
        { fn: "std::panic::catch_unwind", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/panic.rs", line: 146 },
        { fn: "std::thread::Builder::spawn_unchecked_::{{closure}}", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/thread/mod.rs", line: 527 },
        { fn: "core::ops::function::FnOnce::call_once{{vtable.shim}}", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/core/src/ops/function.rs", line: 250 },
        { fn: "<alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/alloc/src/boxed.rs", line: 2020 },
        { fn: "<alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/alloc/src/boxed.rs", line: 2020 },
        { fn: "std::sys::pal::unix::thread::Thread::new::thread_start", file: "/rustc/9b00956e56009bab2aa15d7bff10916599e3d6d6/library/std/src/sys/pal/unix/thread.rs", line: 108 },
        { fn: "start_thread" },
        { fn: "clone" },
    ]"), 
    exec_state: Some(ExecutionState { 
        stack_trace: [
            (Some(ModuleId { address: 63f12417df0177fe3106b899bdd2891112c6ab25b08c4c285ab5d36ee3cd14af, name: Identifier("devices") }), FunctionDefinitionIndex(6), 12), 
            (Some(ModuleId { address: 63f12417df0177fe3106b899bdd2891112c6ab25b08c4c285ab5d36ee3cd14af, name: Identifier("universal_wallet") }), FunctionDefinitionIndex(19), 45)] 
        }), 
    location: Module(ModuleId { address: 0000000000000000000000000000000000000000000000000000000000000001, name: Identifier("table") }), 
    indices: [], 
    offsets: [(FunctionDefinitionIndex(9), 0)] 
}

What error, if any, are you getting?

EXECUTION_LIMIT_REACHED

What have you tried or looked at? Or how can we reproduce the error?

No response

Which operating system are you using?

macOS

Which SDK or tool are you using? (if any)

REST API

Describe your environment or tooling in detail

Running a private blockchain networking consisting of 8 Aptos validators (version 1.16.3, no custom code).

[gregnazario]

Normally, execution gas applied to submitted transactions. There is a max gas limit default for view functions to prevent DoS attacks. It's useful to ensure users don't make full nodes spend all their time running long view functions. But since you're running a private blockchain you can just adjust max_gas_view_function in the config to increase the limit. Similarly if you were running your own full node for the public networks, you can adjust this field to allow you to make more complex view functions.

https://github.com/aptos-labs/aptos-core/blob/main/config/src/config/api_config.rs

Other option is to optimize the function

[byron1st]

Thanks! I will try what you suggested in this comment!