From f2ed89be46adf21b032550acd4831e8fbe1bfeb0 Mon Sep 17 00:00:00 2001 From: arkpar Date: Fri, 5 Feb 2016 22:54:33 +0100 Subject: [PATCH 1/6] Fixed an issue with forked counters --- util/src/journaldb.rs | 90 ++++++++++++++++++++++++++++++------------- 1 file changed, 64 insertions(+), 26 deletions(-) diff --git a/util/src/journaldb.rs b/util/src/journaldb.rs index 810b06727..2173fdeb6 100644 --- a/util/src/journaldb.rs +++ b/util/src/journaldb.rs @@ -20,7 +20,7 @@ use common::*; use rlp::*; use hashdb::*; use memorydb::*; -use rocksdb::{DB, Writable, WriteBatch, IteratorMode}; +use rocksdb::{DB, Writable, WriteBatch, IteratorMode, DBVector}; #[cfg(test)] use std::env; @@ -105,6 +105,11 @@ impl JournalDB { // for each end_era that we journaled that we are no passing by, // we remove all of its removes assuming it is canonical and all // of its inserts otherwise. + // + // we also keep track of the counters for each key inserted in the journal to handle the following cases: + // key K is removed in block A(N) and re-inserted in block B(N + C) (where C < H). K must not be deleted from the DB. + // key K is added in block A(N) and reverted in block B(N + C) (where C < H). K must be deleted + // key K is added in blocks A(N) and A'(N) and is reverted in block B(N + C ) (where C < H). K must not be deleted // record new commit's details. let batch = WriteBatch::new(); @@ -125,6 +130,7 @@ impl JournalDB { let mut r = RlpStream::new_list(3); let inserts: Vec = self.overlay.keys().iter().filter(|&(_, &c)| c > 0).map(|(key, _)| key.clone()).collect(); + // Increase counter for each insrted key no matter if the block is canonical or not. for i in &inserts { *counters.entry(i.clone()).or_insert(0) += 1; } @@ -139,6 +145,7 @@ impl JournalDB { if let Some((end_era, canon_id)) = end { let mut index = 0usize; let mut last; + let mut canon_data: Option = None; while let Some(rlp_data) = try!(self.backing.get({ let mut r = RlpStream::new_list(2); r.append(&end_era); @@ -146,35 +153,26 @@ impl JournalDB { last = r.drain(); &last })) { - let to_add; - let rlp = Rlp::new(&rlp_data); - { - to_add = rlp.val_at(1); - for i in &to_add { - let delete_counter = { - if let Some(mut cnt) = counters.get_mut(i) { - *cnt -= 1; - *cnt == 0 - } - else { false } - - }; - if delete_counter { - counters.remove(i); - } - } + let canon = { + let rlp = Rlp::new(&rlp_data); + if canon_id != rlp.val_at(0) { + let to_add: Vec = rlp.val_at(1); + JournalDB::apply_removes(&to_add, &to_add, &mut counters, &batch); + false + } else { true } + }; + if canon { + canon_data = Some(rlp_data) } - let to_remove: Vec = if canon_id == rlp.val_at(0) {rlp.val_at(2)} else {to_add}; - for i in &to_remove { - if !counters.contains_key(i) { - batch.delete(&i).expect("Low-level database error. Some issue with your hard disk?"); - } - } - try!(batch.delete(&last)); - trace!("JournalDB: delete journal for time #{}.{}, (canon was {}): {} entries", end_era, index, canon_id, to_remove.len()); index += 1; } + // Canon must be commited last to handle a case when counter reaches 0 in a sibling block + if let Some(ref c) = canon_data { + let rlp = Rlp::new(&c); + let deleted = JournalDB::apply_removes(&rlp.val_at::>(1), &rlp.val_at::>(2), &mut counters, &batch); + trace!("JournalDB: delete journal for time #{}.{}, (canon was {}): {} entries", end_era, index, canon_id, deleted); + } try!(batch.put(&LAST_ERA_KEY, &encode(&end_era))); } @@ -200,6 +198,29 @@ impl JournalDB { Ok(ret) } + fn apply_removes(added: &[H256], removed: &[H256], counters: &mut HashMap, batch: &WriteBatch) -> usize { + let mut deleted = 0usize; + // Decrease the counters first + for i in added.iter() { + let delete_counter = { + if let Some(mut cnt) = counters.get_mut(i) { + *cnt -= 1; + *cnt == 0 + } + else { false } + }; + if delete_counter { + counters.remove(i); + } + } + // Remove only if counter reached zero + for i in removed.iter().filter(|i| !counters.contains_key(i)) { + batch.delete(&i).expect("Low-level database error. Some issue with your hard disk?"); + deleted += 1; + } + deleted + } + fn payload(&self, key: &H256) -> Option { self.backing.get(&key.bytes()).expect("Low-level database error. Some issue with your hard disk?").map(|v| v.to_vec()) } @@ -387,4 +408,21 @@ mod tests { jdb.commit(3, &b"2".sha3(), Some((0, b"2".sha3()))).unwrap(); assert!(jdb.exists(&foo)); } + + #[test] + fn fork_same_key() { + // history is 1 + let mut jdb = JournalDB::new_temp(); + jdb.commit(0, &b"0".sha3(), None).unwrap(); + + let foo = jdb.insert(b"foo"); + jdb.commit(1, &b"1a".sha3(), Some((0, b"0".sha3()))).unwrap(); + + jdb.insert(b"foo"); + jdb.commit(1, &b"1b".sha3(), Some((0, b"0".sha3()))).unwrap(); + assert!(jdb.exists(&foo)); + + jdb.commit(2, &b"2a".sha3(), Some((1, b"1a".sha3()))).unwrap(); + assert!(jdb.exists(&foo)); + } } From b2f69a08ca1ecc893f86b39ad5d6f4ded3be95c9 Mon Sep 17 00:00:00 2001 From: arkpar Date: Sun, 7 Feb 2016 11:50:56 +0100 Subject: [PATCH 2/6] Clarified counters --- util/src/journaldb.rs | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/util/src/journaldb.rs b/util/src/journaldb.rs index 2173fdeb6..a2b0981cc 100644 --- a/util/src/journaldb.rs +++ b/util/src/journaldb.rs @@ -106,10 +106,12 @@ impl JournalDB { // we remove all of its removes assuming it is canonical and all // of its inserts otherwise. // - // we also keep track of the counters for each key inserted in the journal to handle the following cases: - // key K is removed in block A(N) and re-inserted in block B(N + C) (where C < H). K must not be deleted from the DB. - // key K is added in block A(N) and reverted in block B(N + C) (where C < H). K must be deleted - // key K is added in blocks A(N) and A'(N) and is reverted in block B(N + C ) (where C < H). K must not be deleted + // we also keep track of the counters for each key inserted in the journal to handle + // the following cases where key K must not be deleted from the DB: + // Given H is the journal size in eras, 0 <= C <= H. + // Key K is removed in era A(N) and re-inserted in canonical era B(N + C). + // Key K is removed in era A(N) and re-inserted in non-canonical era B`(N + C). + // Key K is added in canonical era A(N) and non-canonicnal B'(N + C). // record new commit's details. let batch = WriteBatch::new(); From 976b10a4efa3bb4c1d0c3e16714bcd1dc0071a81 Mon Sep 17 00:00:00 2001 From: arkpar Date: Sun, 7 Feb 2016 12:10:28 +0100 Subject: [PATCH 3/6] Removed warning supression --- util/src/journaldb.rs | 1 - 1 file changed, 1 deletion(-) diff --git a/util/src/journaldb.rs b/util/src/journaldb.rs index a2b0981cc..5d3276631 100644 --- a/util/src/journaldb.rs +++ b/util/src/journaldb.rs @@ -92,7 +92,6 @@ impl JournalDB { /// Commit all recent insert operations and historical removals from the old era /// to the backing database. - #[allow(cyclomatic_complexity)] pub fn commit(&mut self, now: u64, id: &H256, end: Option<(u64, H256)>) -> Result { // journal format: // [era, 0] => [ id, [insert_0, ...], [remove_0, ...] ] From 28dd73e340097615cc3f8b75f9fb73354c2bd397 Mon Sep 17 00:00:00 2001 From: arkpar Date: Sun, 7 Feb 2016 18:28:15 +0100 Subject: [PATCH 4/6] Updated counter comment --- util/src/journaldb.rs | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/util/src/journaldb.rs b/util/src/journaldb.rs index 5d3276631..c13bdee62 100644 --- a/util/src/journaldb.rs +++ b/util/src/journaldb.rs @@ -110,7 +110,7 @@ impl JournalDB { // Given H is the journal size in eras, 0 <= C <= H. // Key K is removed in era A(N) and re-inserted in canonical era B(N + C). // Key K is removed in era A(N) and re-inserted in non-canonical era B`(N + C). - // Key K is added in canonical era A(N) and non-canonicnal B'(N + C). + // Key K is added in non-canonical era A'(N) canonical B(N + C). // record new commit's details. let batch = WriteBatch::new(); From 6c36a7e1a6258643ec8f5f00c1a9d127b9e96401 Mon Sep 17 00:00:00 2001 From: arkpar Date: Sun, 7 Feb 2016 21:18:51 +0100 Subject: [PATCH 5/6] Apply all removes after updating all counters --- util/src/journaldb.rs | 61 +++++++++++++++++++++---------------------- 1 file changed, 30 insertions(+), 31 deletions(-) diff --git a/util/src/journaldb.rs b/util/src/journaldb.rs index c13bdee62..371e60c58 100644 --- a/util/src/journaldb.rs +++ b/util/src/journaldb.rs @@ -20,7 +20,7 @@ use common::*; use rlp::*; use hashdb::*; use memorydb::*; -use rocksdb::{DB, Writable, WriteBatch, IteratorMode, DBVector}; +use rocksdb::{DB, Writable, WriteBatch, IteratorMode}; #[cfg(test)] use std::env; @@ -105,12 +105,16 @@ impl JournalDB { // we remove all of its removes assuming it is canonical and all // of its inserts otherwise. // - // we also keep track of the counters for each key inserted in the journal to handle - // the following cases where key K must not be deleted from the DB: + // We also keep reference counters for each key inserted in the journal to handle + // the following cases where key K must not be deleted from the DB when processing removals : // Given H is the journal size in eras, 0 <= C <= H. // Key K is removed in era A(N) and re-inserted in canonical era B(N + C). // Key K is removed in era A(N) and re-inserted in non-canonical era B`(N + C). // Key K is added in non-canonical era A'(N) canonical B(N + C). + // + // The counter is encreased each time a key is inserted in the journal in the commit. The list of insertions + // is saved with the era record. When the era becomes end_era and goes out of journal the counter is decreased + // and the key is safe to delete. // record new commit's details. let batch = WriteBatch::new(); @@ -131,7 +135,7 @@ impl JournalDB { let mut r = RlpStream::new_list(3); let inserts: Vec = self.overlay.keys().iter().filter(|&(_, &c)| c > 0).map(|(key, _)| key.clone()).collect(); - // Increase counter for each insrted key no matter if the block is canonical or not. + // Increase counter for each inserted key no matter if the block is canonical or not. for i in &inserts { *counters.entry(i.clone()).or_insert(0) += 1; } @@ -146,7 +150,8 @@ impl JournalDB { if let Some((end_era, canon_id)) = end { let mut index = 0usize; let mut last; - let mut canon_data: Option = None; + let mut to_remove: Vec = Vec::new(); + let mut canon_inserts: Vec = Vec::new(); while let Some(rlp_data) = try!(self.backing.get({ let mut r = RlpStream::new_list(2); r.append(&end_era); @@ -154,30 +159,30 @@ impl JournalDB { last = r.drain(); &last })) { - let canon = { - let rlp = Rlp::new(&rlp_data); - if canon_id != rlp.val_at(0) { - let to_add: Vec = rlp.val_at(1); - JournalDB::apply_removes(&to_add, &to_add, &mut counters, &batch); - false - } else { true } - }; - if canon { - canon_data = Some(rlp_data) + let rlp = Rlp::new(&rlp_data); + let inserts: Vec = rlp.val_at(1); + JournalDB::decrease_counters(&inserts, &mut counters); + // Collect keys to be removed. These are removed keys for canonical block, inserted for non-canonical + if canon_id == rlp.val_at(0) { + to_remove.extend(rlp.at(2).iter().map(|r| r.as_val::())); + canon_inserts = inserts; + } + else { + to_remove.extend(inserts); } try!(batch.delete(&last)); index += 1; } - // Canon must be commited last to handle a case when counter reaches 0 in a sibling block - if let Some(ref c) = canon_data { - let rlp = Rlp::new(&c); - let deleted = JournalDB::apply_removes(&rlp.val_at::>(1), &rlp.val_at::>(2), &mut counters, &batch); - trace!("JournalDB: delete journal for time #{}.{}, (canon was {}): {} entries", end_era, index, canon_id, deleted); - } + let canon_inserts = canon_inserts.drain(..).collect::>(); + // Purge removed keys if they are not referenced and not re-inserted in the canon commit + for h in to_remove.iter().filter(|h| !counters.contains_key(h) && !canon_inserts.contains(h)) { + try!(batch.delete(&h)); + } try!(batch.put(&LAST_ERA_KEY, &encode(&end_era))); } + // Commit overlay insertions let mut ret = 0u32; let mut deletes = 0usize; for i in self.overlay.drain().into_iter() { @@ -199,10 +204,10 @@ impl JournalDB { Ok(ret) } - fn apply_removes(added: &[H256], removed: &[H256], counters: &mut HashMap, batch: &WriteBatch) -> usize { - let mut deleted = 0usize; - // Decrease the counters first - for i in added.iter() { + + // Decrease counters for given keys. Deletes obsolete counters + fn decrease_counters(keys: &[H256], counters: &mut HashMap) { + for i in keys.iter() { let delete_counter = { if let Some(mut cnt) = counters.get_mut(i) { *cnt -= 1; @@ -214,12 +219,6 @@ impl JournalDB { counters.remove(i); } } - // Remove only if counter reached zero - for i in removed.iter().filter(|i| !counters.contains_key(i)) { - batch.delete(&i).expect("Low-level database error. Some issue with your hard disk?"); - deleted += 1; - } - deleted } fn payload(&self, key: &H256) -> Option { From 63f2f42035f0bef9b508e74fff73c6b1f3781c59 Mon Sep 17 00:00:00 2001 From: arkpar Date: Sun, 7 Feb 2016 22:16:58 +0100 Subject: [PATCH 6/6] Restored trace --- util/src/journaldb.rs | 3 +++ 1 file changed, 3 insertions(+) diff --git a/util/src/journaldb.rs b/util/src/journaldb.rs index 371e60c58..e805f0a60 100644 --- a/util/src/journaldb.rs +++ b/util/src/journaldb.rs @@ -176,10 +176,13 @@ impl JournalDB { let canon_inserts = canon_inserts.drain(..).collect::>(); // Purge removed keys if they are not referenced and not re-inserted in the canon commit + let mut deletes = 0; for h in to_remove.iter().filter(|h| !counters.contains_key(h) && !canon_inserts.contains(h)) { try!(batch.delete(&h)); + deletes += 1; } try!(batch.put(&LAST_ERA_KEY, &encode(&end_era))); + trace!("JournalDB: delete journal for time #{}.{}, (canon was {}): {} entries", end_era, index, canon_id, deletes); } // Commit overlay insertions