ClickHouse/dbms/Dictionaries/ComplexKeyCacheDictionary.cpp
Ivan 97f2a2213e
Move all folders inside /dbms one level up (#9974)
* Move some code outside dbms/src folder
* Fix paths
2020-04-02 02:51:21 +03:00

428 lines
15 KiB
C++

#include "ComplexKeyCacheDictionary.h"
#include <Common/Arena.h>
#include <Common/BitHelpers.h>
#include <Common/CurrentMetrics.h>
#include <Common/ProfileEvents.h>
#include <Common/ProfilingScopedRWLock.h>
#include <Common/Stopwatch.h>
#include <Common/randomSeed.h>
#include <ext/map.h>
#include <ext/range.h>
#include "DictionaryBlockInputStream.h"
#include "DictionaryFactory.h"
namespace ProfileEvents
{
extern const Event DictCacheKeysRequested;
extern const Event DictCacheKeysRequestedMiss;
extern const Event DictCacheKeysRequestedFound;
extern const Event DictCacheKeysExpired;
extern const Event DictCacheKeysNotFound;
extern const Event DictCacheKeysHit;
extern const Event DictCacheRequestTimeNs;
extern const Event DictCacheLockWriteNs;
extern const Event DictCacheLockReadNs;
}
namespace CurrentMetrics
{
extern const Metric DictCacheRequests;
}
namespace DB
{
namespace ErrorCodes
{
extern const int TYPE_MISMATCH;
extern const int BAD_ARGUMENTS;
extern const int UNSUPPORTED_METHOD;
extern const int TOO_SMALL_BUFFER_SIZE;
}
inline UInt64 ComplexKeyCacheDictionary::getCellIdx(const StringRef key) const
{
const auto hash = StringRefHash{}(key);
const auto idx = hash & size_overlap_mask;
return idx;
}
ComplexKeyCacheDictionary::ComplexKeyCacheDictionary(
const std::string & database_,
const std::string & name_,
const DictionaryStructure & dict_struct_,
DictionarySourcePtr source_ptr_,
const DictionaryLifetime dict_lifetime_,
const size_t size_)
: database(database_)
, name(name_)
, full_name{database_.empty() ? name_ : (database_ + "." + name_)}
, dict_struct(dict_struct_)
, source_ptr{std::move(source_ptr_)}
, dict_lifetime(dict_lifetime_)
, size{roundUpToPowerOfTwoOrZero(std::max(size_, size_t(max_collision_length)))}
, size_overlap_mask{this->size - 1}
, rnd_engine(randomSeed())
{
if (!this->source_ptr->supportsSelectiveLoad())
throw Exception{full_name + ": source cannot be used with ComplexKeyCacheDictionary", ErrorCodes::UNSUPPORTED_METHOD};
createAttributes();
}
void ComplexKeyCacheDictionary::getString(
const std::string & attribute_name, const Columns & key_columns, const DataTypes & key_types, ColumnString * out) const
{
dict_struct.validateKeyTypes(key_types);
auto & attribute = getAttribute(attribute_name);
checkAttributeType(full_name, attribute_name, attribute.type, AttributeUnderlyingType::utString);
const auto null_value = StringRef{std::get<String>(attribute.null_values)};
getItemsString(attribute, key_columns, out, [&](const size_t) { return null_value; });
}
void ComplexKeyCacheDictionary::getString(
const std::string & attribute_name,
const Columns & key_columns,
const DataTypes & key_types,
const ColumnString * const def,
ColumnString * const out) const
{
dict_struct.validateKeyTypes(key_types);
auto & attribute = getAttribute(attribute_name);
checkAttributeType(full_name, attribute_name, attribute.type, AttributeUnderlyingType::utString);
getItemsString(attribute, key_columns, out, [&](const size_t row) { return def->getDataAt(row); });
}
void ComplexKeyCacheDictionary::getString(
const std::string & attribute_name,
const Columns & key_columns,
const DataTypes & key_types,
const String & def,
ColumnString * const out) const
{
dict_struct.validateKeyTypes(key_types);
auto & attribute = getAttribute(attribute_name);
checkAttributeType(full_name, attribute_name, attribute.type, AttributeUnderlyingType::utString);
getItemsString(attribute, key_columns, out, [&](const size_t) { return StringRef{def}; });
}
/// returns cell_idx (always valid for replacing), 'cell is valid' flag, 'cell is outdated' flag,
/// true false found and valid
/// false true not found (something outdated, maybe our cell)
/// false false not found (other id stored with valid data)
/// true true impossible
///
/// todo: split this func to two: find_for_get and find_for_set
ComplexKeyCacheDictionary::FindResult
ComplexKeyCacheDictionary::findCellIdx(const StringRef & key, const CellMetadata::time_point_t now, const size_t hash) const
{
auto pos = hash;
auto oldest_id = pos;
auto oldest_time = CellMetadata::time_point_t::max();
const auto stop = pos + max_collision_length;
for (; pos < stop; ++pos)
{
const auto cell_idx = pos & size_overlap_mask;
const auto & cell = cells[cell_idx];
if (cell.hash != hash || cell.key != key)
{
/// maybe we already found nearest expired cell
if (oldest_time > now && oldest_time > cell.expiresAt())
{
oldest_time = cell.expiresAt();
oldest_id = cell_idx;
}
continue;
}
if (cell.expiresAt() < now)
{
return {cell_idx, false, true};
}
return {cell_idx, true, false};
}
oldest_id &= size_overlap_mask;
return {oldest_id, false, false};
}
void ComplexKeyCacheDictionary::has(const Columns & key_columns, const DataTypes & key_types, PaddedPODArray<UInt8> & out) const
{
dict_struct.validateKeyTypes(key_types);
/// Mapping: <key> -> { all indices `i` of `key_columns` such that `key_columns[i]` = <key> }
MapType<std::vector<size_t>> outdated_keys;
const auto rows_num = key_columns.front()->size();
const auto keys_size = dict_struct.key->size();
StringRefs keys(keys_size);
Arena temporary_keys_pool;
PODArray<StringRef> keys_array(rows_num);
size_t cache_expired = 0, cache_not_found = 0, cache_hit = 0;
{
const ProfilingScopedReadRWLock read_lock{rw_lock, ProfileEvents::DictCacheLockReadNs};
const auto now = std::chrono::system_clock::now();
/// fetch up-to-date values, decide which ones require update
for (const auto row : ext::range(0, rows_num))
{
const StringRef key = placeKeysInPool(row, key_columns, keys, *dict_struct.key, temporary_keys_pool);
keys_array[row] = key;
const auto find_result = findCellIdx(key, now);
const auto & cell_idx = find_result.cell_idx;
/** cell should be updated if either:
* 1. keys (or hash) do not match,
* 2. cell has expired,
* 3. explicit defaults were specified and cell was set default. */
if (!find_result.valid)
{
outdated_keys[key].push_back(row);
if (find_result.outdated)
++cache_expired;
else
++cache_not_found;
}
else
{
++cache_hit;
const auto & cell = cells[cell_idx];
out[row] = !cell.isDefault();
}
}
}
ProfileEvents::increment(ProfileEvents::DictCacheKeysExpired, cache_expired);
ProfileEvents::increment(ProfileEvents::DictCacheKeysNotFound, cache_not_found);
ProfileEvents::increment(ProfileEvents::DictCacheKeysHit, cache_hit);
query_count.fetch_add(rows_num, std::memory_order_relaxed);
hit_count.fetch_add(rows_num - outdated_keys.size(), std::memory_order_release);
if (outdated_keys.empty())
return;
std::vector<size_t> required_rows(outdated_keys.size());
std::transform(
std::begin(outdated_keys), std::end(outdated_keys), std::begin(required_rows), [](auto & pair) { return pair.getMapped().front(); });
/// request new values
update(
key_columns,
keys_array,
required_rows,
[&](const StringRef key, const auto)
{
for (const auto out_idx : outdated_keys[key])
out[out_idx] = true;
},
[&](const StringRef key, const auto)
{
for (const auto out_idx : outdated_keys[key])
out[out_idx] = false;
});
}
void ComplexKeyCacheDictionary::createAttributes()
{
const auto attributes_size = dict_struct.attributes.size();
attributes.reserve(attributes_size);
bytes_allocated += size * sizeof(CellMetadata);
bytes_allocated += attributes_size * sizeof(attributes.front());
for (const auto & attribute : dict_struct.attributes)
{
attribute_index_by_name.emplace(attribute.name, attributes.size());
attributes.push_back(createAttributeWithType(attribute.underlying_type, attribute.null_value));
if (attribute.hierarchical)
throw Exception{full_name + ": hierarchical attributes not supported for dictionary of type " + getTypeName(),
ErrorCodes::TYPE_MISMATCH};
}
}
ComplexKeyCacheDictionary::Attribute & ComplexKeyCacheDictionary::getAttribute(const std::string & attribute_name) const
{
const auto it = attribute_index_by_name.find(attribute_name);
if (it == std::end(attribute_index_by_name))
throw Exception{full_name + ": no such attribute '" + attribute_name + "'", ErrorCodes::BAD_ARGUMENTS};
return attributes[it->second];
}
StringRef ComplexKeyCacheDictionary::allocKey(const size_t row, const Columns & key_columns, StringRefs & keys) const
{
if (key_size_is_fixed)
return placeKeysInFixedSizePool(row, key_columns);
return placeKeysInPool(row, key_columns, keys, *dict_struct.key, *keys_pool);
}
void ComplexKeyCacheDictionary::freeKey(const StringRef key) const
{
if (key_size_is_fixed)
fixed_size_keys_pool->free(const_cast<char *>(key.data));
else
keys_pool->free(const_cast<char *>(key.data), key.size);
}
template <typename Pool>
StringRef ComplexKeyCacheDictionary::placeKeysInPool(
const size_t row, const Columns & key_columns, StringRefs & keys, const std::vector<DictionaryAttribute> & key_attributes, Pool & pool)
{
const auto keys_size = key_columns.size();
size_t sum_keys_size{};
for (size_t j = 0; j < keys_size; ++j)
{
keys[j] = key_columns[j]->getDataAt(row);
sum_keys_size += keys[j].size;
if (key_attributes[j].underlying_type == AttributeUnderlyingType::utString)
sum_keys_size += sizeof(size_t) + 1;
}
auto place = pool.alloc(sum_keys_size);
auto key_start = place;
for (size_t j = 0; j < keys_size; ++j)
{
if (key_attributes[j].underlying_type == AttributeUnderlyingType::utString)
{
auto start = key_start;
auto key_size = keys[j].size + 1;
memcpy(key_start, &key_size, sizeof(size_t));
key_start += sizeof(size_t);
memcpy(key_start, keys[j].data, keys[j].size);
key_start += keys[j].size;
*key_start = '\0';
++key_start;
keys[j].data = start;
keys[j].size += sizeof(size_t) + 1;
}
else
{
memcpy(key_start, keys[j].data, keys[j].size);
keys[j].data = key_start;
key_start += keys[j].size;
}
}
return {place, sum_keys_size};
}
/// Explicit instantiations.
template StringRef ComplexKeyCacheDictionary::placeKeysInPool<Arena>(
const size_t row,
const Columns & key_columns,
StringRefs & keys,
const std::vector<DictionaryAttribute> & key_attributes,
Arena & pool);
template StringRef ComplexKeyCacheDictionary::placeKeysInPool<ArenaWithFreeLists>(
const size_t row,
const Columns & key_columns,
StringRefs & keys,
const std::vector<DictionaryAttribute> & key_attributes,
ArenaWithFreeLists & pool);
StringRef ComplexKeyCacheDictionary::placeKeysInFixedSizePool(const size_t row, const Columns & key_columns) const
{
const auto res = fixed_size_keys_pool->alloc();
auto place = res;
for (const auto & key_column : key_columns)
{
const StringRef key = key_column->getDataAt(row);
memcpy(place, key.data, key.size);
place += key.size;
}
return {res, key_size};
}
StringRef ComplexKeyCacheDictionary::copyIntoArena(StringRef src, Arena & arena)
{
char * allocated = arena.alloc(src.size);
memcpy(allocated, src.data, src.size);
return {allocated, src.size};
}
StringRef ComplexKeyCacheDictionary::copyKey(const StringRef key) const
{
const auto res = key_size_is_fixed ? fixed_size_keys_pool->alloc() : keys_pool->alloc(key.size);
memcpy(res, key.data, key.size);
return {res, key.size};
}
bool ComplexKeyCacheDictionary::isEmptyCell(const UInt64 idx) const
{
return (
cells[idx].key == StringRef{}
&& (idx != zero_cell_idx || cells[idx].data == ext::safe_bit_cast<CellMetadata::time_point_urep_t>(CellMetadata::time_point_t())));
}
BlockInputStreamPtr ComplexKeyCacheDictionary::getBlockInputStream(const Names & column_names, size_t max_block_size) const
{
std::vector<StringRef> keys;
{
const ProfilingScopedReadRWLock read_lock{rw_lock, ProfileEvents::DictCacheLockReadNs};
for (auto idx : ext::range(0, cells.size()))
if (!isEmptyCell(idx) && !cells[idx].isDefault())
keys.push_back(cells[idx].key);
}
using BlockInputStreamType = DictionaryBlockInputStream<ComplexKeyCacheDictionary, UInt64>;
return std::make_shared<BlockInputStreamType>(shared_from_this(), max_block_size, keys, column_names);
}
void registerDictionaryComplexKeyCache(DictionaryFactory & factory)
{
auto create_layout = [=](const std::string & full_name,
const DictionaryStructure & dict_struct,
const Poco::Util::AbstractConfiguration & config,
const std::string & config_prefix,
DictionarySourcePtr source_ptr) -> DictionaryPtr
{
if (!dict_struct.key)
throw Exception{"'key' is required for dictionary of layout 'complex_key_hashed'", ErrorCodes::BAD_ARGUMENTS};
const auto & layout_prefix = config_prefix + ".layout";
const auto size = config.getInt(layout_prefix + ".complex_key_cache.size_in_cells");
if (size == 0)
throw Exception{full_name + ": dictionary of layout 'cache' cannot have 0 cells", ErrorCodes::TOO_SMALL_BUFFER_SIZE};
const bool require_nonempty = config.getBool(config_prefix + ".require_nonempty", false);
if (require_nonempty)
throw Exception{full_name + ": dictionary of layout 'cache' cannot have 'require_nonempty' attribute set",
ErrorCodes::BAD_ARGUMENTS};
const String database = config.getString(config_prefix + ".database", "");
const String name = config.getString(config_prefix + ".name");
const DictionaryLifetime dict_lifetime{config, config_prefix + ".lifetime"};
return std::make_unique<ComplexKeyCacheDictionary>(database, name, dict_struct, std::move(source_ptr), dict_lifetime, size);
};
factory.registerLayout("complex_key_cache", create_layout, true);
}
}