Problem: contract call which does lots of message calls is slow to execute #710

yihuang · 2021-11-01T07:15:16Z

System info: ethermint main

Test Contract

pragma solidity ^0.6.6;

contract Inner {
	event TestEvent(uint256);
    function test() public returns (uint256) {
        emit TestEvent(42);
        return 42;
    }
}

// An contract that do lots of message calls
contract TestMessageCall {
    Inner _inner;
	constructor() public {
        _inner = new Inner();
	}

    function test(uint iterations) public returns (uint256) {
        uint256 n = 0;
        for (uint i=0; i < iterations; i++) {
            n += _inner.test();
        }
        return n;
    }
}

EstimateGas Slow

When call eth_estimateGas for the test(40000) contract method call, the web3 HTTP client timeout, the node log shows it takes 17 seconds to finish.
A single eth_call can be finished in 584ms, and the binary search in estimateGas did ceil(log2(25000000)) = 25 number of calls, it sums up to 25 * 584ms = 14 seconds, close to what we see in the eth_estimateGas call.

Solution:

improve the execution speed of each call
lower the internal gas cap (so out of gas tx will fail earlier, and estimateGas will do less iterations in the worst case).

Tx Execution Slow

Further investigation shows that the actual execution of the tx is even slower, a single run of the tx takes 30 seconds, the profile shows the hotspot is in the commit of a deep context stack.

Solution:

might have to refactor StateDB to use journal log approach like go-ethereum to implement the snapshot/revert.

Expected behavior: RPC API and transactions should return fast

Actual behavior: blocked for dozens of seconds

Additional info:

Compiled contract:
TestMessageCall.json.zip

The text was updated successfully, but these errors were encountered:

yihuang · 2021-11-01T07:27:20Z

I tried same script with geth and same gas limit, it's much faster, the request returns normally:

ValueError: {'code': -32000, 'message': 'gas required exceeds allowance (24926833)'}

leejw51crypto · 2021-11-01T07:55:00Z

how about logging the loop count which calls evm evaluation in binary searching?
time for each call
total call count

maybe too many calls?

starting gas allowance maybe too high?
possible solution is lowering default gas allowances?

yihuang · 2021-11-01T08:25:42Z

how about logging the loop count which calls evm evaluation in binary searching? time for each call total call count

maybe too many calls?

it's the worst case of binary search, so it should be around log2(25000000) = 24.57

starting gas allowance maybe too high? possible solution is lowering default gas allowances?

yeah, possibly, or make the performance closer to go-ethereum.

yihuang · 2021-11-01T08:28:00Z

I did a single eth_call, the logged execution time is 584.998496ms, and 584.998496 * 25 = 14624.9624ms, close to the 17s of estimateGas.

leejw51crypto · 2021-11-01T15:38:09Z

25 times of search count is not bad,
can we reduce evm execution time ?
584 ms == 0.5 seconds

possibly , too many logs from evm calls?
some cost for each state commit? (in running evm)

yihuang · 2021-11-02T04:54:58Z

I did a profile, most of the time are spent on the commit of context stack.

I think we have an O(N*M) (N: depth of context stack, M: number of written items) complexity here, because, for an item set at the top of the stack, when commit, it's not committed directly to initial context, but committed to every context in the stack one by one.

yihuang · 2021-11-02T05:08:16Z

The benchmark is added here: https://github.com/yihuang/ethermint/tree/bench-tx
Profile: go test -v ./x/evm/keeper -v -run="^$" -bench="BenchmarkMessageCall" -cpuprofile profile.out
Benchmark result on my mac:

goos: darwin
goarch: amd64
pkg: github.com/tharsis/ethermint/x/evm/keeper
cpu: Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
BenchmarkMessageCall
BenchmarkMessageCall-16    	       1	30278823164 ns/op

…st (#10486) We can shave off some milliseconds, but also cut down some Megabytes of RAM consumed by only requesting from the cache if needed, but also using the map clearing idiom which is recognized by the compiler to make fast code. Noticed in profiles from Tharsis' Ethermint per evmos/ethermint#710 - Before * Memory profiles ```shell 19.50MB 19.50MB 134: store.cache = make(map[string]*cValue) 18.50MB 18.50MB 135: store.deleted = make(map[string]struct{}) 15.50MB 15.50MB 136: store.unsortedCache = make(map[string]struct{}) ``` * CPU profiles ```go . . 118: // TODO: Consider allowing usage of Batch, which would allow the write to . . 119: // at least happen atomically. 150ms 150ms 120: for _, key := range keys { 220ms 3.64s 121: cacheValue := store.cache[key] . . 122: . . 123: switch { . 250ms 124: case store.isDeleted(key): . . 125: store.parent.Delete([]byte(key)) 210ms 210ms 126: case cacheValue.value == nil: . . 127: // Skip, it already doesn't exist in parent. . . 128: default: 240ms 27.94s 129: store.parent.Set([]byte(key), cacheValue.value) . . 130: } . . 131: } ... 10ms 60ms 134: store.cache = make(map[string]*cValue) . 40ms 135: store.deleted = make(map[string]struct{}) . 50ms 136: store.unsortedCache = make(map[string]struct{}) . 110ms 137: store.sortedCache = dbm.NewMemDB() ``` - After * Memory profiles ```shell . . 130: // Clear the cache using the map clearing idiom . . 131: // and not allocating fresh objects. . . 132: // Please see https://bencher.orijtech.com/perfclinic/mapclearing/ . . 133: for key := range store.cache { . . 134: delete(store.cache, key) . . 135: } . . 136: for key := range store.deleted { . . 137: delete(store.deleted, key) . . 138: } . . 139: for key := range store.unsortedCache { . . 140: delete(store.unsortedCache, key) . . 141: } ``` * CPU profiles ```shell . . 111: // TODO: Consider allowing usage of Batch, which would allow the write to . . 112: // at least happen atomically. 110ms 110ms 113: for _, key := range keys { . 210ms 114: if store.isDeleted(key) { . . 115: // We use []byte(key) instead of conv.UnsafeStrToBytes because we cannot . . 116: // be sure if the underlying store might do a save with the byteslice or . . 117: // not. Once we get confirmation that .Delete is guaranteed not to . . 118: // save the byteslice, then we can assume only a read-only copy is sufficient. . . 119: store.parent.Delete([]byte(key)) . . 120: continue . . 121: } . . 122: 50ms 2.45s 123: cacheValue := store.cache[key] 910ms 920ms 124: if cacheValue.value != nil { . . 125: // It already exists in the parent, hence delete it. 120ms 29.56s 126: store.parent.Set([]byte(key), cacheValue.value) . . 127: } . . 128: } . . 129: . . 130: // Clear the cache using the map clearing idiom . . 131: // and not allocating fresh objects. . . 132: // Please see https://bencher.orijtech.com/perfclinic/mapclearing/ . 210ms 133: for key := range store.cache { . . 134: delete(store.cache, key) . . 135: } . 10ms 136: for key := range store.deleted { . . 137: delete(store.deleted, key) . . 138: } . 170ms 139: for key := range store.unsortedCache { . . 140: delete(store.unsortedCache, key) . . 141: } . 260ms 142: store.sortedCache = dbm.NewMemDB() . 10ms 143:} ``` Fixes #10487 Updates evmos/ethermint#710

…st (cosmos#10486) We can shave off some milliseconds, but also cut down some Megabytes of RAM consumed by only requesting from the cache if needed, but also using the map clearing idiom which is recognized by the compiler to make fast code. Noticed in profiles from Tharsis' Ethermint per evmos/ethermint#710 - Before * Memory profiles ```shell 19.50MB 19.50MB 134: store.cache = make(map[string]*cValue) 18.50MB 18.50MB 135: store.deleted = make(map[string]struct{}) 15.50MB 15.50MB 136: store.unsortedCache = make(map[string]struct{}) ``` * CPU profiles ```go . . 118: // TODO: Consider allowing usage of Batch, which would allow the write to . . 119: // at least happen atomically. 150ms 150ms 120: for _, key := range keys { 220ms 3.64s 121: cacheValue := store.cache[key] . . 122: . . 123: switch { . 250ms 124: case store.isDeleted(key): . . 125: store.parent.Delete([]byte(key)) 210ms 210ms 126: case cacheValue.value == nil: . . 127: // Skip, it already doesn't exist in parent. . . 128: default: 240ms 27.94s 129: store.parent.Set([]byte(key), cacheValue.value) . . 130: } . . 131: } ... 10ms 60ms 134: store.cache = make(map[string]*cValue) . 40ms 135: store.deleted = make(map[string]struct{}) . 50ms 136: store.unsortedCache = make(map[string]struct{}) . 110ms 137: store.sortedCache = dbm.NewMemDB() ``` - After * Memory profiles ```shell . . 130: // Clear the cache using the map clearing idiom . . 131: // and not allocating fresh objects. . . 132: // Please see https://bencher.orijtech.com/perfclinic/mapclearing/ . . 133: for key := range store.cache { . . 134: delete(store.cache, key) . . 135: } . . 136: for key := range store.deleted { . . 137: delete(store.deleted, key) . . 138: } . . 139: for key := range store.unsortedCache { . . 140: delete(store.unsortedCache, key) . . 141: } ``` * CPU profiles ```shell . . 111: // TODO: Consider allowing usage of Batch, which would allow the write to . . 112: // at least happen atomically. 110ms 110ms 113: for _, key := range keys { . 210ms 114: if store.isDeleted(key) { . . 115: // We use []byte(key) instead of conv.UnsafeStrToBytes because we cannot . . 116: // be sure if the underlying store might do a save with the byteslice or . . 117: // not. Once we get confirmation that .Delete is guaranteed not to . . 118: // save the byteslice, then we can assume only a read-only copy is sufficient. . . 119: store.parent.Delete([]byte(key)) . . 120: continue . . 121: } . . 122: 50ms 2.45s 123: cacheValue := store.cache[key] 910ms 920ms 124: if cacheValue.value != nil { . . 125: // It already exists in the parent, hence delete it. 120ms 29.56s 126: store.parent.Set([]byte(key), cacheValue.value) . . 127: } . . 128: } . . 129: . . 130: // Clear the cache using the map clearing idiom . . 131: // and not allocating fresh objects. . . 132: // Please see https://bencher.orijtech.com/perfclinic/mapclearing/ . 210ms 133: for key := range store.cache { . . 134: delete(store.cache, key) . . 135: } . 10ms 136: for key := range store.deleted { . . 137: delete(store.deleted, key) . . 138: } . 170ms 139: for key := range store.unsortedCache { . . 140: delete(store.unsortedCache, key) . . 141: } . 260ms 142: store.sortedCache = dbm.NewMemDB() . 10ms 143:} ``` Fixes cosmos#10487 Updates evmos/ethermint#710

github-actions · 2021-12-18T00:11:24Z

This issue is stale because it has been open 45 days with no activity. Remove Status: Stale label or comment or this will be closed in 7 days.

…st (#10486) We can shave off some milliseconds, but also cut down some Megabytes of RAM consumed by only requesting from the cache if needed, but also using the map clearing idiom which is recognized by the compiler to make fast code. Noticed in profiles from Tharsis' Ethermint per evmos/ethermint#710 - Before * Memory profiles ```shell 19.50MB 19.50MB 134: store.cache = make(map[string]*cValue) 18.50MB 18.50MB 135: store.deleted = make(map[string]struct{}) 15.50MB 15.50MB 136: store.unsortedCache = make(map[string]struct{}) ``` * CPU profiles ```go . . 118: // TODO: Consider allowing usage of Batch, which would allow the write to . . 119: // at least happen atomically. 150ms 150ms 120: for _, key := range keys { 220ms 3.64s 121: cacheValue := store.cache[key] . . 122: . . 123: switch { . 250ms 124: case store.isDeleted(key): . . 125: store.parent.Delete([]byte(key)) 210ms 210ms 126: case cacheValue.value == nil: . . 127: // Skip, it already doesn't exist in parent. . . 128: default: 240ms 27.94s 129: store.parent.Set([]byte(key), cacheValue.value) . . 130: } . . 131: } ... 10ms 60ms 134: store.cache = make(map[string]*cValue) . 40ms 135: store.deleted = make(map[string]struct{}) . 50ms 136: store.unsortedCache = make(map[string]struct{}) . 110ms 137: store.sortedCache = dbm.NewMemDB() ``` - After * Memory profiles ```shell . . 130: // Clear the cache using the map clearing idiom . . 131: // and not allocating fresh objects. . . 132: // Please see https://bencher.orijtech.com/perfclinic/mapclearing/ . . 133: for key := range store.cache { . . 134: delete(store.cache, key) . . 135: } . . 136: for key := range store.deleted { . . 137: delete(store.deleted, key) . . 138: } . . 139: for key := range store.unsortedCache { . . 140: delete(store.unsortedCache, key) . . 141: } ``` * CPU profiles ```shell . . 111: // TODO: Consider allowing usage of Batch, which would allow the write to . . 112: // at least happen atomically. 110ms 110ms 113: for _, key := range keys { . 210ms 114: if store.isDeleted(key) { . . 115: // We use []byte(key) instead of conv.UnsafeStrToBytes because we cannot . . 116: // be sure if the underlying store might do a save with the byteslice or . . 117: // not. Once we get confirmation that .Delete is guaranteed not to . . 118: // save the byteslice, then we can assume only a read-only copy is sufficient. . . 119: store.parent.Delete([]byte(key)) . . 120: continue . . 121: } . . 122: 50ms 2.45s 123: cacheValue := store.cache[key] 910ms 920ms 124: if cacheValue.value != nil { . . 125: // It already exists in the parent, hence delete it. 120ms 29.56s 126: store.parent.Set([]byte(key), cacheValue.value) . . 127: } . . 128: } . . 129: . . 130: // Clear the cache using the map clearing idiom . . 131: // and not allocating fresh objects. . . 132: // Please see https://bencher.orijtech.com/perfclinic/mapclearing/ . 210ms 133: for key := range store.cache { . . 134: delete(store.cache, key) . . 135: } . 10ms 136: for key := range store.deleted { . . 137: delete(store.deleted, key) . . 138: } . 170ms 139: for key := range store.unsortedCache { . . 140: delete(store.unsortedCache, key) . . 141: } . 260ms 142: store.sortedCache = dbm.NewMemDB() . 10ms 143:} ``` Fixes #10487 Updates evmos/ethermint#710 (cherry picked from commit 5399e72) # Conflicts: # CHANGELOG.md

…st, avoid keys sort (backport #10486) (#10848) * perf: store/cachekv: avoid a map lookup if unnecessary, clear maps fast (#10486) We can shave off some milliseconds, but also cut down some Megabytes of RAM consumed by only requesting from the cache if needed, but also using the map clearing idiom which is recognized by the compiler to make fast code. Noticed in profiles from Tharsis' Ethermint per evmos/ethermint#710 - Before * Memory profiles ```shell 19.50MB 19.50MB 134: store.cache = make(map[string]*cValue) 18.50MB 18.50MB 135: store.deleted = make(map[string]struct{}) 15.50MB 15.50MB 136: store.unsortedCache = make(map[string]struct{}) ``` * CPU profiles ```go . . 118: // TODO: Consider allowing usage of Batch, which would allow the write to . . 119: // at least happen atomically. 150ms 150ms 120: for _, key := range keys { 220ms 3.64s 121: cacheValue := store.cache[key] . . 122: . . 123: switch { . 250ms 124: case store.isDeleted(key): . . 125: store.parent.Delete([]byte(key)) 210ms 210ms 126: case cacheValue.value == nil: . . 127: // Skip, it already doesn't exist in parent. . . 128: default: 240ms 27.94s 129: store.parent.Set([]byte(key), cacheValue.value) . . 130: } . . 131: } ... 10ms 60ms 134: store.cache = make(map[string]*cValue) . 40ms 135: store.deleted = make(map[string]struct{}) . 50ms 136: store.unsortedCache = make(map[string]struct{}) . 110ms 137: store.sortedCache = dbm.NewMemDB() ``` - After * Memory profiles ```shell . . 130: // Clear the cache using the map clearing idiom . . 131: // and not allocating fresh objects. . . 132: // Please see https://bencher.orijtech.com/perfclinic/mapclearing/ . . 133: for key := range store.cache { . . 134: delete(store.cache, key) . . 135: } . . 136: for key := range store.deleted { . . 137: delete(store.deleted, key) . . 138: } . . 139: for key := range store.unsortedCache { . . 140: delete(store.unsortedCache, key) . . 141: } ``` * CPU profiles ```shell . . 111: // TODO: Consider allowing usage of Batch, which would allow the write to . . 112: // at least happen atomically. 110ms 110ms 113: for _, key := range keys { . 210ms 114: if store.isDeleted(key) { . . 115: // We use []byte(key) instead of conv.UnsafeStrToBytes because we cannot . . 116: // be sure if the underlying store might do a save with the byteslice or . . 117: // not. Once we get confirmation that .Delete is guaranteed not to . . 118: // save the byteslice, then we can assume only a read-only copy is sufficient. . . 119: store.parent.Delete([]byte(key)) . . 120: continue . . 121: } . . 122: 50ms 2.45s 123: cacheValue := store.cache[key] 910ms 920ms 124: if cacheValue.value != nil { . . 125: // It already exists in the parent, hence delete it. 120ms 29.56s 126: store.parent.Set([]byte(key), cacheValue.value) . . 127: } . . 128: } . . 129: . . 130: // Clear the cache using the map clearing idiom . . 131: // and not allocating fresh objects. . . 132: // Please see https://bencher.orijtech.com/perfclinic/mapclearing/ . 210ms 133: for key := range store.cache { . . 134: delete(store.cache, key) . . 135: } . 10ms 136: for key := range store.deleted { . . 137: delete(store.deleted, key) . . 138: } . 170ms 139: for key := range store.unsortedCache { . . 140: delete(store.unsortedCache, key) . . 141: } . 260ms 142: store.sortedCache = dbm.NewMemDB() . 10ms 143:} ``` Fixes #10487 Updates evmos/ethermint#710 (cherry picked from commit 5399e72) # Conflicts: # CHANGELOG.md * fix conflicts Co-authored-by: Emmanuel T Odeke <emmanuel@orijtech.com> Co-authored-by: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>

…st, avoid keys sort (backport cosmos#10486) (cosmos#10848) * perf: store/cachekv: avoid a map lookup if unnecessary, clear maps fast (cosmos#10486) We can shave off some milliseconds, but also cut down some Megabytes of RAM consumed by only requesting from the cache if needed, but also using the map clearing idiom which is recognized by the compiler to make fast code. Noticed in profiles from Tharsis' Ethermint per evmos/ethermint#710 - Before * Memory profiles ```shell 19.50MB 19.50MB 134: store.cache = make(map[string]*cValue) 18.50MB 18.50MB 135: store.deleted = make(map[string]struct{}) 15.50MB 15.50MB 136: store.unsortedCache = make(map[string]struct{}) ``` * CPU profiles ```go . . 118: // TODO: Consider allowing usage of Batch, which would allow the write to . . 119: // at least happen atomically. 150ms 150ms 120: for _, key := range keys { 220ms 3.64s 121: cacheValue := store.cache[key] . . 122: . . 123: switch { . 250ms 124: case store.isDeleted(key): . . 125: store.parent.Delete([]byte(key)) 210ms 210ms 126: case cacheValue.value == nil: . . 127: // Skip, it already doesn't exist in parent. . . 128: default: 240ms 27.94s 129: store.parent.Set([]byte(key), cacheValue.value) . . 130: } . . 131: } ... 10ms 60ms 134: store.cache = make(map[string]*cValue) . 40ms 135: store.deleted = make(map[string]struct{}) . 50ms 136: store.unsortedCache = make(map[string]struct{}) . 110ms 137: store.sortedCache = dbm.NewMemDB() ``` - After * Memory profiles ```shell . . 130: // Clear the cache using the map clearing idiom . . 131: // and not allocating fresh objects. . . 132: // Please see https://bencher.orijtech.com/perfclinic/mapclearing/ . . 133: for key := range store.cache { . . 134: delete(store.cache, key) . . 135: } . . 136: for key := range store.deleted { . . 137: delete(store.deleted, key) . . 138: } . . 139: for key := range store.unsortedCache { . . 140: delete(store.unsortedCache, key) . . 141: } ``` * CPU profiles ```shell . . 111: // TODO: Consider allowing usage of Batch, which would allow the write to . . 112: // at least happen atomically. 110ms 110ms 113: for _, key := range keys { . 210ms 114: if store.isDeleted(key) { . . 115: // We use []byte(key) instead of conv.UnsafeStrToBytes because we cannot . . 116: // be sure if the underlying store might do a save with the byteslice or . . 117: // not. Once we get confirmation that .Delete is guaranteed not to . . 118: // save the byteslice, then we can assume only a read-only copy is sufficient. . . 119: store.parent.Delete([]byte(key)) . . 120: continue . . 121: } . . 122: 50ms 2.45s 123: cacheValue := store.cache[key] 910ms 920ms 124: if cacheValue.value != nil { . . 125: // It already exists in the parent, hence delete it. 120ms 29.56s 126: store.parent.Set([]byte(key), cacheValue.value) . . 127: } . . 128: } . . 129: . . 130: // Clear the cache using the map clearing idiom . . 131: // and not allocating fresh objects. . . 132: // Please see https://bencher.orijtech.com/perfclinic/mapclearing/ . 210ms 133: for key := range store.cache { . . 134: delete(store.cache, key) . . 135: } . 10ms 136: for key := range store.deleted { . . 137: delete(store.deleted, key) . . 138: } . 170ms 139: for key := range store.unsortedCache { . . 140: delete(store.unsortedCache, key) . . 141: } . 260ms 142: store.sortedCache = dbm.NewMemDB() . 10ms 143:} ``` Fixes cosmos#10487 Updates evmos/ethermint#710 (cherry picked from commit 5399e72) # Conflicts: # CHANGELOG.md * fix conflicts Co-authored-by: Emmanuel T Odeke <emmanuel@orijtech.com> Co-authored-by: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>

yihuang changed the title ~~Problem: An estimateGas request is very slow to execute~~ Problem: contract with lots of message call is slow Nov 2, 2021

yihuang changed the title ~~Problem: contract with lots of message call is slow~~ Problem: contract call which does lots of message calls is slow to execute Nov 2, 2021

yihuang mentioned this issue Nov 2, 2021

benchmark evm message calls #717

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odeke-em mentioned this issue Nov 2, 2021

perf: store/cachekv: avoid a map lookup if unnecessary, clear maps fast, avoid keys sort cosmos/cosmos-sdk#10486

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This was referenced Nov 2, 2021

Problem: EVM keeper keeps intermediate states inside #663

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Problem: contract call which does lots of message calls is slow to execute #729

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tomtau mentioned this issue Nov 9, 2021

Iterator time is exponential in number of Cache wrappings cosmos/cosmos-sdk#10310

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github-actions bot added the Status: Stale label Dec 18, 2021

github-actions bot closed this as completed Dec 25, 2021

allthatjazzleo mentioned this issue Jan 14, 2022

Problem: cronosd high disk io consumption crypto-org-chain/cronos#291

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Problem: contract call which does lots of message calls is slow to execute #710

Problem: contract call which does lots of message calls is slow to execute #710

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Problem: contract call which does lots of message calls is slow to execute #710

Problem: contract call which does lots of message calls is slow to execute #710

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yihuang commented Nov 1, 2021 • edited

Test Contract

EstimateGas Slow

Tx Execution Slow

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