feat: Regression based modelling of gas prices

[bvrooman]

Related issues:

• Separate DependentCost into LightOperation and HeavyOperation  fuel-vm#611
• Investigate approaches for improved modelling of predicted gas prices  #1522

[bvrooman]

There are some outstanding issues that I will address presently. But the PR is ready for a first round of reviews. I will do a new VM release with required cost changes and integrate. I will also upgrade the Rust version, as well as other tangential changes, in separate PRs.

[xgreenx]

I'm curious about which values this change produces =)

[xgreenx]

I guess we need it back?=D

[bvrooman]

I removed this section because it is unclear to me how this will be used going forward, or if we still use it in our current benchmark process. This code is designed not to be used when generating formatted output (e.g., -f rust) so we don't use it, and it is just unmaintained code after this point.

[xgreenx]

Do we need so huge input=D?

[bvrooman]

In general, the more data we have during function estimation, the more accurate it will be. In these tests, we see if we can determine an appropriate function from the data set, and the estimation process is sensitive to the quality of the data. Because these tests are pretty strict, (i.e, we test for exact values for slope and intercept) we need to provide enough data to achieve that accuracy.

[bvrooman]

Given the current PR, and the data provided here, collect gives us the following:

use super::*;
/// File generated by fuel-core: benches/src/collect/state.rs:197. With the following git hash
pub const GIT: &str = "856f763cc042e78e6aa215e60614827b0e6cb812";
pub fn default_gas_costs() -> GasCostsValues {
    GasCostsValues {
        add: 1,
        addi: 1,
        aloc: 1,
        and: 1,
        andi: 1,
        bal: 832,
        bhei: 1,
        bhsh: 1,
        burn: 73630,
        cb: 1,
        cfei: 1,
        cfsi: 1,
        croo: 173,
        div: 1,
        divi: 1,
        eck1: 3849,
        ecr1: 51685,
        ed19: 3783,
        eq: 1,
        exp: 1,
        expi: 1,
        flag: 1,
        gm: 1,
        gt: 1,
        gtf: 1,
        ji: 1,
        jmp: 1,
        jne: 1,
        jnei: 1,
        jnzi: 1,
        jmpf: 1,
        jmpb: 1,
        jnzf: 1,
        jnzb: 1,
        jnef: 1,
        jneb: 1,
        lb: 1,
        log: 1503,
        lt: 1,
        lw: 1,
        mint: 58278,
        mlog: 2,
        state_root: DependentCost::HeavyOperation {
            base: 0,
            gas_per_unit: 186,
        },
        modi: 1,
        mod_op: 1,
        movi: 1,
        mroo: 4,
        mul: 1,
        muli: 1,
        mldv: 1,
        noop: 1,
        not: 1,
        or: 1,
        ori: 1,
        poph: 1,
        popl: 1,
        pshh: 1,
        pshl: 1,
        move_op: 1,
        ret: 1687,
        sb: 1,
        sll: 1,
        slli: 1,
        srl: 1,
        srli: 1,
        srw: 41,
        sub: 1,
        subi: 1,
        sw: 1,
        sww: 1253,
        time: 1,
        tr: 120175,
        tro: 72174,
        wdcm: 1,
        wqcm: 2,
        wdop: 2,
        wqop: 2,
        wdml: 2,
        wqml: 3,
        wddv: 5,
        wqdv: 9,
        wdmd: 11,
        wqmd: 19,
        wdam: 9,
        wqam: 11,
        wdmm: 14,
        wqmm: 14,
        xor: 1,
        xori: 1,
        call: DependentCost::LightOperation {
            base: 11852,
            units_per_gas: 11,
        },
        ccp: DependentCost::LightOperation {
            base: 137,
            units_per_gas: 31,
        },
        csiz: DependentCost::LightOperation {
            base: 150,
            units_per_gas: 57,
        },
        k256: DependentCost::LightOperation {
            base: 23,
            units_per_gas: 3,
        },
        ldc: DependentCost::LightOperation {
            base: 142,
            units_per_gas: 32,
        },
        logd: DependentCost::LightOperation {
            base: 1575,
            units_per_gas: 2,
        },
        mcl: DependentCost::LightOperation {
            base: 0,
            units_per_gas: 538,
        },
        mcli: DependentCost::LightOperation {
            base: 0,
            units_per_gas: 548,
        },
        mcp: DependentCost::LightOperation {
            base: 0,
            units_per_gas: 448,
        },
        mcpi: DependentCost::LightOperation {
            base: 2,
            units_per_gas: 1824,
        },
        meq: DependentCost::LightOperation {
            base: 1,
            units_per_gas: 1104,
        },
        rvrt: 1742,
        s256: DependentCost::LightOperation {
            base: 10,
            units_per_gas: 3,
        },
        scwq: DependentCost::HeavyOperation {
            base: 1,
            gas_per_unit: 0,
        },
        smo: DependentCost::LightOperation {
            base: 71020,
            units_per_gas: 2,
        },
        srwq: DependentCost::LightOperation {
            base: 0,
            units_per_gas: 1,
        },
        swwq: DependentCost::HeavyOperation {
            base: 1,
            gas_per_unit: 0,
        },
        contract_root: DependentCost::LightOperation {
            base: 0,
            units_per_gas: 3,
        },
        retd: DependentCost::LightOperation {
            base: 1583,
            units_per_gas: 2,
        },
    }
}

Note that scwq and swwq were not included:

Warning the following keys were not set by this bench:
["jmpb", "jmpf", "jneb", "jnef", "jnzb", "jnzf", "mldv", "poph", "popl", "pshh", "pshl", "scwq", "swwq"]

[MitchTurner]

I'm curious why you went with something that warms the CPU here. From what I'm reading I assume this is meant to be some arbitrary process. I would usually choose to do a sleep--or better something that mocks time. Maybe it's a constraint from criterion?

Also, I think a more descriptive name might be useful here. I inferred the use from the lack of output--it might be nice to name it something like consume_cpu_resources or do_arbitrary_work or something like that.

[MitchTurner]

This looks great. Just had one clarifying question.

[xgreenx]

I like the idea of this change, it looks great=)

I want to block the merging of this PR until we have stable results from the collect binary that we can use in production.

Right now it doesn't return prices for sequential opcodes.

[bvrooman]

I like the idea of this change, it looks great=)

I want to block the merging of this PR until we have stable results from the collect binary that we can use in production.

Right now it doesn't return prices for sequential opcodes.

Can you clarify which sequential opcodes are not returned by this version of collect please? I can investigate that.

Edit: If you're referring to the fact that the above results do not include scwq and swwq, it's simply because the benchmark data I used to generate the prices did not include them. They were generated from this data as provided on Slack.

[bvrooman]

Updated prices:

use super::*;
/// File generated by fuel-core: benches/src/collect/state.rs:197. With the following git hash
pub const GIT: &str = "12c044d226407e230b7653251dd381e15f5f5462";
pub fn default_gas_costs() -> GasCostsValues {
    GasCostsValues {
        add: 1,
        addi: 1,
        aloc: 0,
        and: 1,
        andi: 1,
        bal: 40,
        bhei: 1,
        bhsh: 1,
        burn: 27737,
        cb: 1,
        cfei: 1,
        cfsi: 1,
        croo: 39,
        div: 1,
        divi: 1,
        eck1: 3106,
        ecr1: 42737,
        ed19: 2896,
        eq: 1,
        exp: 1,
        expi: 1,
        flag: 0,
        gm: 1,
        gt: 1,
        gtf: 1,
        ji: 1,
        jmp: 1,
        jne: 1,
        jnei: 1,
        jnzi: 1,
        jmpf: 1,
        jmpb: 1,
        jnzf: 1,
        jnzb: 1,
        jnef: 1,
        jneb: 1,
        lb: 1,
        log: 86,
        lt: 1,
        lw: 1,
        mint: 25514,
        mlog: 1,
        state_root: DependentCost::HeavyOperation {
            base: 0,
            gas_per_unit: 161,
        },
        modi: 1,
        mod_op: 1,
        movi: 1,
        mroo: 3,
        mul: 1,
        muli: 1,
        mldv: 3,
        noop: 1,
        not: 1,
        or: 1,
        ori: 1,
        poph: 2,
        popl: 2,
        pshh: 2,
        pshl: 2,
        move_op: 1,
        ret: 126,
        sb: 1,
        sll: 1,
        slli: 1,
        srl: 1,
        srli: 1,
        srw: 223,
        sub: 1,
        subi: 1,
        sw: 1,
        sww: 26246,
        time: 75,
        tr: 38924,
        tro: 26755,
        wdcm: 1,
        wqcm: 2,
        wdop: 2,
        wqop: 2,
        wdml: 2,
        wqml: 3,
        wddv: 4,
        wqdv: 5,
        wdmd: 9,
        wqmd: 16,
        wdam: 8,
        wqam: 10,
        wdmm: 9,
        wqmm: 9,
        xor: 1,
        xori: 1,
        call: DependentCost::LightOperation {
            base: 16160,
            units_per_gas: 60,
        },
        ccp: DependentCost::LightOperation {
            base: 20,
            units_per_gas: 23,
        },
        csiz: DependentCost::LightOperation {
            base: 28,
            units_per_gas: 300,
        },
        k256: DependentCost::LightOperation {
            base: 27,
            units_per_gas: 4,
        },
        ldc: DependentCost::LightOperation {
            base: 18,
            units_per_gas: 73,
        },
        logd: DependentCost::LightOperation {
            base: 124,
            units_per_gas: 3,
        },
        mcl: DependentCost::LightOperation {
            base: 0,
            units_per_gas: 639,
        },
        mcli: DependentCost::LightOperation {
            base: 0,
            units_per_gas: 639,
        },
        mcp: DependentCost::LightOperation {
            base: 1,
            units_per_gas: 523,
        },
        mcpi: DependentCost::HeavyOperation {
            base: 2,
            gas_per_unit: 0,
        },
        meq: DependentCost::LightOperation {
            base: 1,
            units_per_gas: 1349,
        },
        rvrt: 126,
        s256: DependentCost::LightOperation {
            base: 20,
            units_per_gas: 3,
        },
        scwq: DependentCost::HeavyOperation {
            base: 2093854,
            gas_per_unit: 21099,
        },
        smo: DependentCost::LightOperation {
            base: 26672,
            units_per_gas: 3,
        },
        srwq: DependentCost::HeavyOperation {
            base: 410,
            gas_per_unit: 19,
        },
        swwq: DependentCost::HeavyOperation {
            base: 1503569,
            gas_per_unit: 20088,
        },
        contract_root: DependentCost::LightOperation {
            base: 0,
            units_per_gas: 3,
        },
        retd: DependentCost::LightOperation {
            base: 145,
            units_per_gas: 3,
        },
    }
}