memory leak in crypto/merkle (?) #3313
Description
Running a default single node causes the memory to grow.
Inspecting the difference in heap dumps as the memory grows suggests there's a leak in the use of the Merkle tree.
Running a very simple test confirms this.
For instance this code:
package main
import (
"fmt"
"net/http"
_ "net/http/pprof"
"runtime"
"github.com/tendermint/tendermint/crypto/merkle"
)
func main() {
runtime.MemProfileRate = 1
fmt.Println("vim-go")
list := [][]byte{
[]byte("hello"),
[]byte("goodbye"),
[]byte("ok"),
}
myFunc(list)
runtime.GC()
http.ListenAndServe("localhost:7070", nil)
fmt.Println(list)
}
func myFunc(list [][]byte) {
merkle.SimpleHashFromByteSlices(list)
}
Leaves many of these such entries in the heap profile:
0: 0 [1: 80] @ 0x1408c93 0x140c888 0x140ceff 0x140cda2 0x102f167 0x105d5a1
# 0x1408c92 github.com/tendermint/tendermint/crypto/merkle.innerHash+0x162 /Users/ethanbuchman/programming/goApps/src/github.com/tendermint/tendermint/crypto/merkle/hash.go:20
# 0x140c887 github.com/tendermint/tendermint/crypto/merkle.SimpleHashFromByteSlices+0x137 /Users/ethanbuchman/programming/goApps/src/github.com/tendermint/tendermint/crypto/merkle/simple_tree.go:19
# 0x140cefe main.myFunc+0x3e /Users/ethanbuchman/programming/goApps/src/github.com/tendermint/tendermint/pprof/main.go:27
# 0x140cda1 main.main+0x1f1 /Users/ethanbuchman/programming/goApps/src/github.com/tendermint/tendermint/pprof/main.go:20
# 0x102f166 runtime.main+0x206 /Users/ethanbuchman/goRoot/1.11.5/src/runtime/proc.go:201