This PR creates a global hasher pool that can be used by all packages.
It also removes a bunch of the package local pools.
It also updates a few locations to use available hashers or the global
hashing pool to reduce allocations all over the codebase.
This change should reduce global allocation count by ~1%
---------
Co-authored-by: Gary Rong <garyrong0905@gmail.com>
This pull request removes the node copy operation to reduce memory
allocation. Key Changes as below:
**(a) Use `decodeNodeUnsafe` for decoding nodes retrieved from the trie
node reader**
In the current implementation of the MPT, once a trie node blob is
retrieved, it is passed to `decodeNode` for decoding. However,
`decodeNode` assumes the supplied byte slice might be mutated later, so
it performs a deep copy internally before parsing the node.
Given that the node reader is implemented by the path database and the
hash database, both of which guarantee the immutability of the returned
byte slice. By restricting the node reader interface to explicitly
guarantee that the returned byte slice will not be modified, we can
safely replace `decodeNode` with `decodeNodeUnsafe`. This eliminates the
need for a redundant byte copy during each node resolution.
**(b) Modify the trie in place**
In the current implementation of the MPT, a copy of a trie node is
created before any modifications are made. These modifications include:
- Node resolution: Converting the value from a hash to the actual node.
- Node hashing: Tagging the hash into its cache.
- Node commit: Replacing the children with its hash.
- Structural changes: For example, adding a new child to a fullNode or
replacing a child of a shortNode.
This mechanism ensures that modifications only affect the live tree,
leaving all previously created copies unaffected.
Unfortunately, this property leads to a huge memory allocation
requirement. For example, if we want to modify the fullNode for n times,
the node will be copied for n times.
In this pull request, all the trie modifications are made in place. In
order to make sure all previously created copies are unaffected, the
`Copy` function now will deep-copy all the live nodes rather than the
root node itself.
With this change, while the `Copy` function becomes more expensive, it's
totally acceptable as it's not a frequently used one. For the normal
trie operations (Get, GetNode, Hash, Commit, Insert, Delete), the node
copy is not required anymore.
This changes the CI / release builds to use the latest Go version. It also
upgrades golangci-lint to a newer version compatible with Go 1.19.
In Go 1.19, godoc has gained official support for links and lists. The
syntax for code blocks in doc comments has changed and now requires a
leading tab character. gofmt adapts comments to the new syntax
automatically, so there are a lot of comment re-formatting changes in this
PR. We need to apply the new format in order to pass the CI lint stage with
Go 1.19.
With the linter upgrade, I have decided to disable 'gosec' - it produces
too many false-positive warnings. The 'deadcode' and 'varcheck' linters
have also been removed because golangci-lint warns about them being
unmaintained. 'unused' provides similar coverage and we already have it
enabled, so we don't lose much with this change.
This change speeds up trie hashing and all other activities that require
RLP encoding of trie nodes by approximately 20%. The speedup is achieved by
avoiding reflection overhead during node encoding.
The interface type trie.node now contains a method 'encode' that works with
rlp.EncoderBuffer. Management of EncoderBuffers is left to calling code.
trie.hasher, which is pooled to avoid allocations, now maintains an
EncoderBuffer. This means memory resources related to trie node encoding
are tied to the hasher pool.
Co-authored-by: Felix Lange <fjl@twurst.com>
* trie: update tests to check commit integrity
* trie: polish committer
* trie: fix typo
* trie: remove hasvalue notion
According to the benchmarks, type assertion between the pointer and
interface is extremely fast.
BenchmarkIntmethod-12 1000000000 1.91 ns/op
BenchmarkInterface-12 1000000000 2.13 ns/op
BenchmarkTypeSwitch-12 1000000000 1.81 ns/op
BenchmarkTypeAssertion-12 2000000000 1.78 ns/op
So the overhead for asserting whether the shortnode has "valuenode"
child is super tiny. No necessary to have another field.
* trie: linter nitpicks
Co-authored-by: Martin Holst Swende <martin@swende.se>
* core, crypto: various allocation savings regarding tx handling
* core: reduce allocs for gas price comparison
This change reduces the allocations needed for comparing different transactions to each other.
A call to `tx.GasPrice()` copies the gas price as it has to be safe against modifications and
also needs to be threadsafe. For comparing and ordering different transactions we don't need
these guarantees
* core: added tx.GasPriceIntCmp for comparison without allocation
adds a method to remove unneeded allocation in comparison to tx.gasPrice
* core/types: pool legacykeccak256 objects in rlpHash
rlpHash is by far the most used function in core that allocates a legacyKeccak256 object on each call.
Since it is so widely used it makes sense to add pooling here so we relieve the GC.
On my machine these changes result in > 100 MILLION less allocations and > 30 GB less allocated memory.
* reverted some changes
* reverted some changes
* trie: use crypto.KeccakState instead of replicating code
Co-authored-by: Martin Holst Swende <martin@swende.se>
The current trie memory database/cache that we do pruning on stores
trie nodes as binary rlp encoded blobs, and also stores the node
relationships/references for GC purposes. However, most of the trie
nodes (everything apart from a value node) is in essence just a
collection of references.
This PR switches out the RLP encoded trie blobs with the
collapsed-but-not-serialized trie nodes. This permits most of the
references to be recovered from within the node data structure,
avoiding the need to track them a second time (expensive memory wise).
* trie: make fullnode children hash calculation concurrently
* trie: thread out only on topmost fullnode
* trie: clean up full node children hash calculation
* trie: minor code fixups
Commit 40cdcf1183 broke the optimisation which kept nodes resolved
during Get in the trie. The decoder assigned cache generation 0
unconditionally, causing resolved nodes to get flushed on Commit.
This commit fixes it and adds two tests.
* trie: store nodes as pointers
This avoids memory copies when unwrapping node interface values.
name old time/op new time/op delta
Get 388ns ± 8% 215ns ± 2% -44.56% (p=0.000 n=15+15)
GetDB 363ns ± 3% 202ns ± 2% -44.21% (p=0.000 n=15+15)
UpdateBE 1.57µs ± 2% 1.29µs ± 3% -17.80% (p=0.000 n=13+15)
UpdateLE 1.92µs ± 2% 1.61µs ± 2% -16.25% (p=0.000 n=14+14)
HashBE 2.16µs ± 6% 2.18µs ± 6% ~ (p=0.436 n=15+15)
HashLE 7.43µs ± 3% 7.21µs ± 3% -2.96% (p=0.000 n=15+13)
* trie: close temporary databases in GetDB benchmark
* trie: don't keep []byte from DB load around
Nodes decoded from a DB load kept hashes and values as sub-slices of
the DB value. This can be a problem because loading from leveldb often
returns []byte with a cap that's larger than necessary, increasing
memory usage.
* trie: unload old cached nodes
* trie, core/state: use cache unloading for account trie
* trie: use explicit private flags (fixes Go 1.5 reflection issue).
* trie: fixup cachegen overflow at request of nick
* core/state: rename journal size constant