Files
scylladb/cdc/split.cc
Piotr Dulikowski 338e473946 cdc: fix non-atomic updates in splitting
This patch fixes a bug in mutation splitting logic of CDC. In the part
that handles updates of non-atomic clustering columns, the column
definition was fetched from a static column of the same id instead of
the actual definition of the clustering column. It could cause the value
to be written to a wrong column.

Tests: unit(dev)
2020-03-23 13:47:23 +01:00

464 lines
17 KiB
C++

/*
* Copyright (C) 2020 ScyllaDB
*/
/*
* This file is part of Scylla.
*
* Scylla is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Scylla is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Scylla. If not, see <http://www.gnu.org/licenses/>.
*/
#include "mutation.hh"
#include "schema.hh"
#include "split.hh"
#include "log.hh"
struct atomic_column_update {
column_id id;
atomic_cell cell;
};
// see the comment inside `clustered_row_insert` for motivation for separating
// nonatomic deletions from nonatomic updates
struct nonatomic_column_deletion {
column_id id;
tombstone t;
};
struct nonatomic_column_update {
column_id id;
utils::chunked_vector<std::pair<bytes, atomic_cell>> cells;
};
struct static_row_update {
gc_clock::duration ttl;
std::vector<atomic_column_update> atomic_entries;
std::vector<nonatomic_column_deletion> nonatomic_deletions;
std::vector<nonatomic_column_update> nonatomic_updates;
};
struct clustered_row_insert {
gc_clock::duration ttl;
clustering_key key;
row_marker marker;
std::vector<atomic_column_update> atomic_entries;
std::vector<nonatomic_column_deletion> nonatomic_deletions;
// INSERTs can't express updates of individual cells inside a non-atomic
// (without deleting the entire field first), so no `nonatomic_updates` field
// overwriting a nonatomic column inside an INSERT will be split into two changes:
// one with a nonatomic deletion, and one with a nonatomic update
};
struct clustered_row_update {
gc_clock::duration ttl;
clustering_key key;
std::vector<atomic_column_update> atomic_entries;
std::vector<nonatomic_column_deletion> nonatomic_deletions;
std::vector<nonatomic_column_update> nonatomic_updates;
};
struct clustered_row_deletion {
clustering_key key;
tombstone t;
};
struct clustered_range_deletion {
range_tombstone rt;
};
struct partition_deletion {
tombstone t;
};
struct batch {
std::vector<static_row_update> static_updates;
std::vector<clustered_row_insert> clustered_inserts;
std::vector<clustered_row_update> clustered_updates;
std::vector<clustered_row_deletion> clustered_row_deletions;
std::vector<clustered_range_deletion> clustered_range_deletions;
std::optional<partition_deletion> partition_deletions;
};
using set_of_changes = std::map<api::timestamp_type, batch>;
struct row_update {
std::vector<atomic_column_update> atomic_entries;
std::vector<nonatomic_column_deletion> nonatomic_deletions;
std::vector<nonatomic_column_update> nonatomic_updates;
};
static
std::map<std::pair<api::timestamp_type, gc_clock::duration>, row_update>
extract_row_updates(const row& r, column_kind ckind, const schema& schema) {
std::map<std::pair<api::timestamp_type, gc_clock::duration>, row_update> result;
r.for_each_cell([&] (column_id id, const atomic_cell_or_collection& cell) {
auto& cdef = schema.column_at(ckind, id);
if (cdef.is_atomic()) {
auto view = cell.as_atomic_cell(cdef);
auto timestamp_and_ttl = std::pair(
view.timestamp(),
view.is_live_and_has_ttl() ? view.ttl() : gc_clock::duration(0)
);
result[timestamp_and_ttl].atomic_entries.push_back({id, atomic_cell(*cdef.type, view)});
return;
}
cell.as_collection_mutation().with_deserialized(*cdef.type, [&] (collection_mutation_view_description mview) {
auto desc = mview.materialize(*cdef.type);
for (auto& [k, v]: desc.cells) {
auto timestamp_and_ttl = std::pair(
v.timestamp(),
v.is_live_and_has_ttl() ? v.ttl() : gc_clock::duration(0)
);
auto& updates = result[timestamp_and_ttl].nonatomic_updates;
if (updates.empty() || updates.back().id != id) {
updates.push_back({id, {}});
}
updates.back().cells.push_back({std::move(k), std::move(v)});
}
if (desc.tomb) {
auto timestamp_and_ttl = std::pair(desc.tomb.timestamp, gc_clock::duration(0));
result[timestamp_and_ttl].nonatomic_deletions.push_back({id, desc.tomb});
}
});
});
return result;
};
set_of_changes extract_changes(const mutation& base_mutation, const schema& base_schema) {
set_of_changes res;
auto& p = base_mutation.partition();
auto sr_updates = extract_row_updates(p.static_row().get(), column_kind::static_column, base_schema);
for (auto& [k, up]: sr_updates) {
auto [timestamp, ttl] = k;
res[timestamp].static_updates.push_back({
ttl,
std::move(up.atomic_entries),
std::move(up.nonatomic_deletions),
std::move(up.nonatomic_updates)
});
}
for (const rows_entry& cr : p.clustered_rows()) {
auto cr_updates = extract_row_updates(cr.row().cells(), column_kind::regular_column, base_schema);
const auto& marker = cr.row().marker();
auto marker_timestamp = marker.timestamp();
auto marker_ttl = marker.is_expiring() ? marker.ttl() : gc_clock::duration(0);
if (marker.is_live()) {
// make sure that an entry corresponding to the row marker's timestamp and ttl is in the map
(void)cr_updates[std::pair(marker_timestamp, marker_ttl)];
}
auto is_insert = [&] (api::timestamp_type timestamp, gc_clock::duration ttl) {
if (!marker.is_live()) {
return false;
}
return timestamp == marker_timestamp && ttl == marker_ttl;
};
for (auto& [k, up]: cr_updates) {
auto [timestamp, ttl] = k;
if (is_insert(timestamp, ttl)) {
res[timestamp].clustered_inserts.push_back({
ttl,
cr.key(),
marker,
std::move(up.atomic_entries),
std::move(up.nonatomic_deletions)
});
if (!up.nonatomic_updates.empty()) {
// nonatomic updates cannot be expressed with an INSERT.
res[timestamp].clustered_updates.push_back({
ttl,
cr.key(),
{},
{},
std::move(up.nonatomic_updates)
});
}
} else {
res[timestamp].clustered_updates.push_back({
ttl,
cr.key(),
std::move(up.atomic_entries),
std::move(up.nonatomic_deletions),
std::move(up.nonatomic_updates)
});
}
}
auto row_tomb = cr.row().deleted_at().regular();
if (row_tomb) {
res[row_tomb.timestamp].clustered_row_deletions.push_back({cr.key(), row_tomb});
}
}
for (const auto& rt: p.row_tombstones()) {
if (rt.tomb.timestamp != api::missing_timestamp) {
res[rt.tomb.timestamp].clustered_range_deletions.push_back({rt});
}
}
auto partition_tomb_timestamp = p.partition_tombstone().timestamp;
if (partition_tomb_timestamp != api::missing_timestamp) {
res[partition_tomb_timestamp].partition_deletions = {p.partition_tombstone()};
}
return res;
}
namespace cdc {
bool should_split(const mutation& base_mutation, const schema& base_schema) {
auto& p = base_mutation.partition();
api::timestamp_type found_ts = api::missing_timestamp;
std::optional<gc_clock::duration> found_ttl; // 0 = "no ttl"
auto check_or_set = [&] (api::timestamp_type ts, gc_clock::duration ttl) {
if (found_ts != api::missing_timestamp && found_ts != ts) {
return true;
}
found_ts = ts;
if (found_ttl && *found_ttl != ttl) {
return true;
}
found_ttl = ttl;
return false;
};
bool had_static_row = false;
bool should_split = false;
p.static_row().get().for_each_cell([&] (column_id id, const atomic_cell_or_collection& cell) {
had_static_row = true;
auto& cdef = base_schema.column_at(column_kind::static_column, id);
if (cdef.is_atomic()) {
auto view = cell.as_atomic_cell(cdef);
if (check_or_set(view.timestamp(), view.is_live_and_has_ttl() ? view.ttl() : gc_clock::duration(0))) {
should_split = true;
}
return;
}
cell.as_collection_mutation().with_deserialized(*cdef.type, [&] (collection_mutation_view_description mview) {
auto desc = mview.materialize(*cdef.type);
for (auto& [k, v]: desc.cells) {
if (check_or_set(v.timestamp(), v.is_live_and_has_ttl() ? v.ttl() : gc_clock::duration(0))) {
should_split = true;
return;
}
}
if (desc.tomb) {
if (check_or_set(desc.tomb.timestamp, gc_clock::duration(0))) {
should_split = true;
return;
}
}
});
});
if (should_split) {
return true;
}
bool had_clustered_row = false;
if (!p.clustered_rows().empty() && had_static_row) {
return true;
}
for (const rows_entry& cr : p.clustered_rows()) {
had_clustered_row = true;
const auto& marker = cr.row().marker();
if (marker.is_live() && check_or_set(marker.timestamp(), marker.is_expiring() ? marker.ttl() : gc_clock::duration(0))) {
return true;
}
bool is_insert = marker.is_live();
bool had_cells = false;
cr.row().cells().for_each_cell([&] (column_id id, const atomic_cell_or_collection& cell) {
had_cells = true;
auto& cdef = base_schema.column_at(column_kind::regular_column, id);
if (cdef.is_atomic()) {
auto view = cell.as_atomic_cell(cdef);
if (check_or_set(view.timestamp(), view.is_live_and_has_ttl() ? view.ttl() : gc_clock::duration(0))) {
should_split = true;
}
return;
}
cell.as_collection_mutation().with_deserialized(*cdef.type, [&] (collection_mutation_view_description mview) {
for (auto& [k, v]: mview.cells) {
if (check_or_set(v.timestamp(), v.is_live_and_has_ttl() ? v.ttl() : gc_clock::duration(0))) {
should_split = true;
return;
}
if (is_insert) {
// nonatomic updates cannot be expressed with an INSERT.
should_split = true;
return;
}
}
if (mview.tomb) {
if (check_or_set(mview.tomb.timestamp, gc_clock::duration(0))) {
should_split = true;
return;
}
}
});
});
if (should_split) {
return true;
}
auto row_tomb = cr.row().deleted_at().regular();
if (row_tomb) {
if (had_cells) {
return true;
}
// there were no cells, so no ttl
assert(!found_ttl);
if (found_ts != api::missing_timestamp && found_ts != row_tomb.timestamp) {
return true;
}
found_ts = row_tomb.timestamp;
}
}
if (!p.row_tombstones().empty() && (had_static_row || had_clustered_row)) {
return true;
}
for (const auto& rt: p.row_tombstones()) {
if (rt.tomb) {
if (found_ts != api::missing_timestamp && found_ts != rt.tomb.timestamp) {
return true;
}
found_ts = rt.tomb.timestamp;
}
}
if (p.partition_tombstone().timestamp != api::missing_timestamp
&& (!p.row_tombstones().empty() || had_static_row || had_clustered_row)) {
return true;
}
// A mutation with no timestamp will be split into 0 mutations
return found_ts == api::missing_timestamp;
}
void for_each_change(const mutation& base_mutation, const schema_ptr& base_schema,
seastar::noncopyable_function<void(mutation, api::timestamp_type, bytes, int&)> f) {
auto changes = extract_changes(base_mutation, *base_schema);
auto pk = base_mutation.key();
for (auto& [change_ts, btch] : changes) {
auto tuuid = timeuuid_type->decompose(generate_timeuuid(change_ts));
int batch_no = 0;
for (auto& sr_update : btch.static_updates) {
mutation m(base_schema, pk);
for (auto& atomic_update : sr_update.atomic_entries) {
auto& cdef = base_schema->column_at(column_kind::static_column, atomic_update.id);
m.set_static_cell(cdef, std::move(atomic_update.cell));
}
for (auto& nonatomic_delete : sr_update.nonatomic_deletions) {
auto& cdef = base_schema->column_at(column_kind::static_column, nonatomic_delete.id);
m.set_static_cell(cdef, collection_mutation_description{nonatomic_delete.t, {}}.serialize(*cdef.type));
}
for (auto& nonatomic_update : sr_update.nonatomic_updates) {
auto& cdef = base_schema->column_at(column_kind::static_column, nonatomic_update.id);
m.set_static_cell(cdef, collection_mutation_description{{}, std::move(nonatomic_update.cells)}.serialize(*cdef.type));
}
f(std::move(m), change_ts, tuuid, batch_no);
}
for (auto& cr_insert : btch.clustered_inserts) {
mutation m(base_schema, pk);
auto& row = m.partition().clustered_row(*base_schema, cr_insert.key);
for (auto& atomic_update : cr_insert.atomic_entries) {
auto& cdef = base_schema->column_at(column_kind::regular_column, atomic_update.id);
row.cells().apply(cdef, std::move(atomic_update.cell));
}
for (auto& nonatomic_delete : cr_insert.nonatomic_deletions) {
auto& cdef = base_schema->column_at(column_kind::regular_column, nonatomic_delete.id);
row.cells().apply(cdef, collection_mutation_description{nonatomic_delete.t, {}}.serialize(*cdef.type));
}
row.apply(cr_insert.marker);
f(std::move(m), change_ts, tuuid, batch_no);
}
for (auto& cr_update : btch.clustered_updates) {
mutation m(base_schema, pk);
auto& row = m.partition().clustered_row(*base_schema, cr_update.key).cells();
for (auto& atomic_update : cr_update.atomic_entries) {
auto& cdef = base_schema->column_at(column_kind::regular_column, atomic_update.id);
row.apply(cdef, std::move(atomic_update.cell));
}
for (auto& nonatomic_delete : cr_update.nonatomic_deletions) {
auto& cdef = base_schema->column_at(column_kind::regular_column, nonatomic_delete.id);
row.apply(cdef, collection_mutation_description{nonatomic_delete.t, {}}.serialize(*cdef.type));
}
for (auto& nonatomic_update : cr_update.nonatomic_updates) {
auto& cdef = base_schema->column_at(column_kind::regular_column, nonatomic_update.id);
row.apply(cdef, collection_mutation_description{{}, std::move(nonatomic_update.cells)}.serialize(*cdef.type));
}
f(std::move(m), change_ts, tuuid, batch_no);
}
for (auto& cr_delete : btch.clustered_row_deletions) {
mutation m(base_schema, pk);
m.partition().apply_delete(*base_schema, cr_delete.key, cr_delete.t);
f(std::move(m), change_ts, tuuid, batch_no);
}
for (auto& crange_delete : btch.clustered_range_deletions) {
mutation m(base_schema, pk);
m.partition().apply_delete(*base_schema, crange_delete.rt);
f(std::move(m), change_ts, tuuid, batch_no);
}
if (btch.partition_deletions) {
mutation m(base_schema, pk);
m.partition().apply(btch.partition_deletions->t);
f(std::move(m), change_ts, tuuid, batch_no);
}
}
}
} // namespace cdc