Merge pull request #17111 from karalabe/trie-memleak

trie: fix a temporary memory leak in the memcache
This commit is contained in:
Péter Szilágyi 2018-07-03 17:20:58 +03:00 committed by GitHub
commit 67a7857124
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@ -466,7 +466,13 @@ func (db *Database) dereference(child common.Hash, parent common.Hash) {
return return
} }
// If there are no more references to the child, delete it and cascade // If there are no more references to the child, delete it and cascade
node.parents-- if node.parents > 0 {
// This is a special cornercase where a node loaded from disk (i.e. not in the
// memcache any more) gets reinjected as a new node (short node split into full,
// then reverted into short), causing a cached node to have no parents. That is
// no problem in itself, but don't make maxint parents out of it.
node.parents--
}
if node.parents == 0 { if node.parents == 0 {
// Remove the node from the flush-list // Remove the node from the flush-list
if child == db.oldest { if child == db.oldest {
@ -717,3 +723,45 @@ func (db *Database) Size() (common.StorageSize, common.StorageSize) {
var flushlistSize = common.StorageSize((len(db.nodes) - 1) * 2 * common.HashLength) var flushlistSize = common.StorageSize((len(db.nodes) - 1) * 2 * common.HashLength)
return db.nodesSize + flushlistSize, db.preimagesSize return db.nodesSize + flushlistSize, db.preimagesSize
} }
// verifyIntegrity is a debug method to iterate over the entire trie stored in
// memory and check whether every node is reachable from the meta root. The goal
// is to find any errors that might cause memory leaks and or trie nodes to go
// missing.
//
// This method is extremely CPU and memory intensive, only use when must.
func (db *Database) verifyIntegrity() {
// Iterate over all the cached nodes and accumulate them into a set
reachable := map[common.Hash]struct{}{{}: {}}
for child := range db.nodes[common.Hash{}].children {
db.accumulate(child, reachable)
}
// Find any unreachable but cached nodes
unreachable := []string{}
for hash, node := range db.nodes {
if _, ok := reachable[hash]; !ok {
unreachable = append(unreachable, fmt.Sprintf("%x: {Node: %v, Parents: %d, Prev: %x, Next: %x}",
hash, node.node, node.parents, node.flushPrev, node.flushNext))
}
}
if len(unreachable) != 0 {
panic(fmt.Sprintf("trie cache memory leak: %v", unreachable))
}
}
// accumulate iterates over the trie defined by hash and accumulates all the
// cached children found in memory.
func (db *Database) accumulate(hash common.Hash, reachable map[common.Hash]struct{}) {
// Mark the node reachable if present in the memory cache
node, ok := db.nodes[hash]
if !ok {
return
}
reachable[hash] = struct{}{}
// Iterate over all the children and accumulate them too
for _, child := range node.childs() {
db.accumulate(child, reachable)
}
}