dolysis
/
rocksdb
mirror of https://github.com/facebook/rocksdb.git
3
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Turn compaction asserts to runtime check (#5935) 

Summary:
Compaction iterator has many assert statements that are active only during test runs. Some rare bugs would show up only at runtime could violate the assert condition but go unnoticed since assert statements are not compiled in release mode. Turning the assert statements to runtime check sone pors and cons:
Pros:
- A bug that would result into incorrect data would be detected early before the incorrect data is written to the disk.

Cons:
- Runtime overhead: which should be negligible since compaction cpu is the minority in the overall cpu usage
- The assert statements might already being violated at runtime, and turning them to runtime failure might result into reliability issues.

The patch takes a conservative step in this direction by logging the assert violations at runtime. If we see any violation reported in logs, we investigate. Otherwise, we can go ahead turning them to runtime error.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5935

Differential Revision: D18229697

Pulled By: maysamyabandeh

fbshipit-source-id: f1890eca80ccd7cca29737f1825badb9aa8038a8
This commit is contained in:
Maysam Yabandeh 2019-10-30 13:47:08 -07:00 committed by Facebook Github Bot
parent 0337d87b42
commit dccaf9f03c
3 changed files with 70 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

66
db/compaction/compaction_iterator.cc
View File

@ -3,6 +3,8 @@
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#include <cinttypes>
#include "db/compaction/compaction_iterator.h"
#include "db/snapshot_checker.h"
#include "port/likely.h"
@ -38,7 +40,8 @@ CompactionIterator::CompactionIterator(
const CompactionFilter* compaction_filter,
const std::atomic<bool>* shutting_down,
const SequenceNumber preserve_deletes_seqnum,
const std::atomic<bool>* manual_compaction_paused)
const std::atomic<bool>* manual_compaction_paused,
const std::shared_ptr<Logger> info_log)
: CompactionIterator(
input, cmp, merge_helper, last_sequence, snapshots,
earliest_write_conflict_snapshot, snapshot_checker, env,
@ -46,7 +49,7 @@ CompactionIterator::CompactionIterator(
std::unique_ptr<CompactionProxy>(
compaction ? new CompactionProxy(compaction) : nullptr),
compaction_filter, shutting_down, preserve_deletes_seqnum,
manual_compaction_paused) {}
manual_compaction_paused, info_log) {}
CompactionIterator::CompactionIterator(
InternalIterator* input, const Comparator* cmp, MergeHelper* merge_helper,
@ -59,7 +62,8 @@ CompactionIterator::CompactionIterator(
const CompactionFilter* compaction_filter,
const std::atomic<bool>* shutting_down,
const SequenceNumber preserve_deletes_seqnum,
const std::atomic<bool>* manual_compaction_paused)
const std::atomic<bool>* manual_compaction_paused,
const std::shared_ptr<Logger> info_log)
: input_(input),
cmp_(cmp),
merge_helper_(merge_helper),
@ -78,7 +82,8 @@ CompactionIterator::CompactionIterator(
current_user_key_sequence_(0),
current_user_key_snapshot_(0),
merge_out_iter_(merge_helper_),
current_key_committed_(false) {
current_key_committed_(false),
info_log_(info_log) {
assert(compaction_filter_ == nullptr || compaction_ != nullptr);
assert(snapshots_ != nullptr);
bottommost_level_ =
@ -142,6 +147,11 @@ void CompactionIterator::Next() {
// MergeUntil stops when it encounters a corrupt key and does not
// include them in the result, so we expect the keys here to be valid.
assert(valid_key);
if (!valid_key) {
ROCKS_LOG_FATAL(info_log_, "Invalid key (%s) in compaction",
key_.ToString(true).c_str());
}
// Keep current_key_ in sync.
current_key_.UpdateInternalKey(ikey_.sequence, ikey_.type);
key_ = current_key_.GetInternalKey();
@ -338,7 +348,18 @@ void CompactionIterator::NextFromInput() {
// not compact out. We will keep this Put, but can drop it's data.
// (See Optimization 3, below.)
assert(ikey_.type == kTypeValue);
if (ikey_.type != kTypeValue) {
ROCKS_LOG_FATAL(info_log_,
"Unexpected key type %d for compaction output",
ikey_.type);
}
assert(current_user_key_snapshot_ == last_snapshot);
if (current_user_key_snapshot_ != last_snapshot) {
ROCKS_LOG_FATAL(info_log_,
"current_user_key_snapshot_ (%" PRIu64
") != last_snapshot (%" PRIu64 ")",
current_user_key_snapshot_, last_snapshot);
}
value_.clear();
valid_ = true;
@ -480,6 +501,12 @@ void CompactionIterator::NextFromInput() {
// checking since there has already been a record returned for this key
// in this snapshot.
assert(last_sequence >= current_user_key_sequence_);
if (last_sequence < current_user_key_sequence_) {
ROCKS_LOG_FATAL(info_log_,
"last_sequence (%" PRIu64
") < current_user_key_sequence_ (%" PRIu64 ")",
last_sequence, current_user_key_sequence_);
}
++iter_stats_.num_record_drop_hidden; // (A)
input_->Next();
@ -563,6 +590,10 @@ void CompactionIterator::NextFromInput() {
// MergeUntil stops when it encounters a corrupt key and does not
// include them in the result, so we expect the keys here to valid.
assert(valid_key);
if (!valid_key) {
ROCKS_LOG_FATAL(info_log_, "Invalid key (%s) in compaction",
key_.ToString(true).c_str());
}
// Keep current_key_ in sync.
current_key_.UpdateInternalKey(ikey_.sequence, ikey_.type);
key_ = current_key_.GetInternalKey();
@ -623,6 +654,11 @@ void CompactionIterator::PrepareOutput() {
ikeyNotNeededForIncrementalSnapshot() && bottommost_level_ && valid_ &&
IN_EARLIEST_SNAPSHOT(ikey_.sequence) && ikey_.type != kTypeMerge) {
assert(ikey_.type != kTypeDeletion && ikey_.type != kTypeSingleDeletion);
if (ikey_.type == kTypeDeletion || ikey_.type == kTypeSingleDeletion) {
ROCKS_LOG_FATAL(info_log_,
"Unexpected key type %d for seq-zero optimization",
ikey_.type);
}
ikey_.sequence = 0;
current_key_.UpdateInternalKey(0, ikey_.type);
}
@ -631,6 +667,10 @@ void CompactionIterator::PrepareOutput() {
inline SequenceNumber CompactionIterator::findEarliestVisibleSnapshot(
SequenceNumber in, SequenceNumber* prev_snapshot) {
assert(snapshots_->size());
if (snapshots_->size() == 0) {
ROCKS_LOG_FATAL(info_log_,
"No snapshot left in findEarliestVisibleSnapshot");
}
auto snapshots_iter = std::lower_bound(
snapshots_->begin(), snapshots_->end(), in);
if (snapshots_iter == snapshots_->begin()) {
@ -638,6 +678,10 @@ inline SequenceNumber CompactionIterator::findEarliestVisibleSnapshot(
} else {
*prev_snapshot = *std::prev(snapshots_iter);
assert(*prev_snapshot < in);
if (*prev_snapshot >= in) {
ROCKS_LOG_FATAL(info_log_,
"*prev_snapshot >= in in findEarliestVisibleSnapshot");
}
}
if (snapshot_checker_ == nullptr) {
return snapshots_iter != snapshots_->end()
@ -647,6 +691,9 @@ inline SequenceNumber CompactionIterator::findEarliestVisibleSnapshot(
for (; snapshots_iter != snapshots_->end(); ++snapshots_iter) {
auto cur = *snapshots_iter;
assert(in <= cur);
if (in > cur) {
ROCKS_LOG_FATAL(info_log_, "in > cur in findEarliestVisibleSnapshot");
}
// Skip if cur is in released_snapshots.
if (has_released_snapshot && released_snapshots_.count(cur) > 0) {
continue;
@ -671,9 +718,14 @@ inline bool CompactionIterator::ikeyNotNeededForIncrementalSnapshot() {
bool CompactionIterator::IsInEarliestSnapshot(SequenceNumber sequence) {
assert(snapshot_checker_ != nullptr);
assert(earliest_snapshot_ == kMaxSequenceNumber ||
bool pre_condition = (earliest_snapshot_ == kMaxSequenceNumber ||
(earliest_snapshot_iter_ != snapshots_->end() &&
*earliest_snapshot_iter_ == earliest_snapshot_));
assert(pre_condition);
if (!pre_condition) {
ROCKS_LOG_FATAL(info_log_,
"Pre-Condition is not hold in IsInEarliestSnapshot");
}
auto in_snapshot =
snapshot_checker_->CheckInSnapshot(sequence, earliest_snapshot_);
while (UNLIKELY(in_snapshot == SnapshotCheckerResult::kSnapshotReleased)) {
@ -692,6 +744,10 @@ bool CompactionIterator::IsInEarliestSnapshot(SequenceNumber sequence) {
snapshot_checker_->CheckInSnapshot(sequence, earliest_snapshot_);
}
assert(in_snapshot != SnapshotCheckerResult::kSnapshotReleased);
if (in_snapshot == SnapshotCheckerResult::kSnapshotReleased) {
ROCKS_LOG_FATAL(info_log_,
"Unexpected released snapshot in IsInEarliestSnapshot");
}
return in_snapshot == SnapshotCheckerResult::kInSnapshot;
}

7
db/compaction/compaction_iterator.h
View File

@ -70,7 +70,8 @@ class CompactionIterator {
const CompactionFilter* compaction_filter = nullptr,
const std::atomic<bool>* shutting_down = nullptr,
const SequenceNumber preserve_deletes_seqnum = 0,
const std::atomic<bool>* manual_compaction_paused = nullptr);
const std::atomic<bool>* manual_compaction_paused = nullptr,
const std::shared_ptr<Logger> info_log = nullptr);
// Constructor with custom CompactionProxy, used for tests.
CompactionIterator(
@ -84,7 +85,8 @@ class CompactionIterator {
const CompactionFilter* compaction_filter = nullptr,
const std::atomic<bool>* shutting_down = nullptr,
const SequenceNumber preserve_deletes_seqnum = 0,
const std::atomic<bool>* manual_compaction_paused = nullptr);
const std::atomic<bool>* manual_compaction_paused = nullptr,
const std::shared_ptr<Logger> info_log = nullptr);
~CompactionIterator();
@ -222,6 +224,7 @@ class CompactionIterator {
// Used to avoid purging uncommitted values. The application can specify
// uncommitted values by providing a SnapshotChecker object.
bool current_key_committed_;
std::shared_ptr<Logger> info_log_;
bool IsShuttingDown() {
// This is a best-effort facility, so memory_order_relaxed is sufficient.

3
db/compaction/compaction_job.cc
View File

@ -891,7 +891,8 @@ void CompactionJob::ProcessKeyValueCompaction(SubcompactionState* sub_compact) {
&existing_snapshots_, earliest_write_conflict_snapshot_,
snapshot_checker_, env_, ShouldReportDetailedTime(env_, stats_), false,
&range_del_agg, sub_compact->compaction, compaction_filter,
shutting_down_, preserve_deletes_seqnum_, manual_compaction_paused_));
shutting_down_, preserve_deletes_seqnum_, manual_compaction_paused_,
db_options_.info_log));
auto c_iter = sub_compact->c_iter.get();
c_iter->SeekToFirst();
if (c_iter->Valid() && sub_compact->compaction->output_level() != 0) {