mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-18 21:51:57 +00:00
355 lines
11 KiB
C++
355 lines
11 KiB
C++
#pragma once
|
||
|
||
#include <DB/DataStreams/IProfilingBlockInputStream.h>
|
||
#include <DB/Storages/MergeTree/MergeTreeData.h>
|
||
#include <DB/Storages/MergeTree/PKCondition.h>
|
||
#include <DB/Storages/MergeTree/MergeTreeReader.h>
|
||
#include <DB/Storages/MergeTree/MergeTreeReadPool.h>
|
||
|
||
|
||
namespace DB
|
||
{
|
||
|
||
|
||
/** Used in conjunction with MergeTreeReadPool, asking it for more work to do and performing whatever reads it is asked
|
||
* to perform. */
|
||
class MergeTreeThreadBlockInputStream : public IProfilingBlockInputStream
|
||
{
|
||
/// "thread" index (there are N threads and each thread is assigned index in interval [0..N-1])
|
||
std::size_t thread;
|
||
public:
|
||
MergeTreeThreadBlockInputStream(
|
||
const std::size_t thread,
|
||
const MergeTreeReadPoolPtr & pool, const std::size_t min_marks_to_read, const std::size_t block_size,
|
||
MergeTreeData & storage, const bool use_uncompressed_cache, const ExpressionActionsPtr & prewhere_actions,
|
||
const String & prewhere_column, const Settings & settings, const Names & virt_column_names)
|
||
: thread{thread}, pool{pool}, block_size_marks{block_size / storage.index_granularity},
|
||
/// round min_marks_to_read up to nearest multiple of block_size expressed in marks
|
||
min_marks_to_read{block_size
|
||
? (min_marks_to_read * storage.index_granularity + block_size - 1)
|
||
/ block_size * block_size / storage.index_granularity
|
||
: min_marks_to_read
|
||
},
|
||
storage{storage}, use_uncompressed_cache{use_uncompressed_cache}, prewhere_actions{prewhere_actions},
|
||
prewhere_column{prewhere_column}, min_bytes_to_use_direct_io{settings.min_bytes_to_use_direct_io},
|
||
max_read_buffer_size{settings.max_read_buffer_size}, virt_column_names{virt_column_names},
|
||
log{&Logger::get("MergeTreeThreadBlockInputStream")}
|
||
{}
|
||
|
||
String getName() const override { return "MergeTreeThread"; }
|
||
|
||
String getID() const override
|
||
{
|
||
std::stringstream res;
|
||
/// @todo print some meaningful information
|
||
// res << "MergeTreeThread(columns";
|
||
//
|
||
// for (const auto & column : columns)
|
||
// res << ", " << column.name;
|
||
//
|
||
// if (prewhere_actions)
|
||
// res << ", prewhere, " << prewhere_actions->getID();
|
||
//
|
||
// res << ", marks";
|
||
//
|
||
// for (size_t i = 0; i < all_mark_ranges.size(); ++i)
|
||
// res << ", " << all_mark_ranges[i].begin << ", " << all_mark_ranges[i].end;
|
||
//
|
||
// res << ")";
|
||
return res.str();
|
||
}
|
||
|
||
protected:
|
||
/// Будем вызывать progressImpl самостоятельно.
|
||
void progress(const Progress & value) override {}
|
||
|
||
Block readImpl() override
|
||
{
|
||
Block res;
|
||
|
||
while (!res && !isCancelled())
|
||
{
|
||
if (!task && !getNewTask())
|
||
break;
|
||
|
||
res = readFromPart();
|
||
|
||
if (res)
|
||
injectVirtualColumns(res);
|
||
|
||
if (task->mark_ranges.empty())
|
||
task = {};
|
||
}
|
||
|
||
return res;
|
||
}
|
||
|
||
private:
|
||
/// Requests read task from MergeTreeReadPool and signals whether it got one
|
||
bool getNewTask()
|
||
{
|
||
task = pool->getTask(min_marks_to_read, thread);
|
||
|
||
if (!task)
|
||
{
|
||
/** Закрываем файлы (ещё до уничтожения объекта).
|
||
* Чтобы при создании многих источников, но одновременном чтении только из нескольких,
|
||
* буферы не висели в памяти. */
|
||
reader = {};
|
||
pre_reader = {};
|
||
return false;
|
||
}
|
||
|
||
const auto path = storage.getFullPath() + task->data_part->name + '/';
|
||
|
||
if (!reader)
|
||
{
|
||
if (use_uncompressed_cache)
|
||
owned_uncompressed_cache = storage.context.getUncompressedCache();
|
||
|
||
owned_mark_cache = storage.context.getMarkCache();
|
||
|
||
reader = std::make_unique<MergeTreeReader>(
|
||
path, task->data_part, task->columns, owned_uncompressed_cache.get(), owned_mark_cache.get(),
|
||
storage, task->mark_ranges, min_bytes_to_use_direct_io, max_read_buffer_size);
|
||
|
||
if (prewhere_actions)
|
||
pre_reader = std::make_unique<MergeTreeReader>(
|
||
path, task->data_part, task->pre_columns, owned_uncompressed_cache.get(),
|
||
owned_mark_cache.get(), storage, task->mark_ranges, min_bytes_to_use_direct_io,
|
||
max_read_buffer_size);
|
||
}
|
||
else
|
||
{
|
||
/// retain avg_value_size_hints
|
||
reader = std::make_unique<MergeTreeReader>(
|
||
path, task->data_part, task->columns, owned_uncompressed_cache.get(), owned_mark_cache.get(),
|
||
storage, task->mark_ranges, min_bytes_to_use_direct_io, max_read_buffer_size,
|
||
reader->getAvgValueSizeHints());
|
||
|
||
if (prewhere_actions)
|
||
pre_reader = std::make_unique<MergeTreeReader>(
|
||
path, task->data_part, task->pre_columns, owned_uncompressed_cache.get(),
|
||
owned_mark_cache.get(), storage, task->mark_ranges, min_bytes_to_use_direct_io,
|
||
max_read_buffer_size, pre_reader->getAvgValueSizeHints());
|
||
}
|
||
|
||
return true;
|
||
}
|
||
|
||
Block readFromPart()
|
||
{
|
||
Block res;
|
||
|
||
if (prewhere_actions)
|
||
{
|
||
do
|
||
{
|
||
/// Прочитаем полный блок столбцов, нужных для вычисления выражения в PREWHERE.
|
||
size_t space_left = std::max(1LU, block_size_marks);
|
||
MarkRanges ranges_to_read;
|
||
while (!task->mark_ranges.empty() && space_left)
|
||
{
|
||
auto & range = task->mark_ranges.back();
|
||
|
||
size_t marks_to_read = std::min(range.end - range.begin, space_left);
|
||
pre_reader->readRange(range.begin, range.begin + marks_to_read, res);
|
||
|
||
ranges_to_read.emplace_back(range.begin, range.begin + marks_to_read);
|
||
space_left -= marks_to_read;
|
||
range.begin += marks_to_read;
|
||
if (range.begin == range.end)
|
||
task->mark_ranges.pop_back();
|
||
}
|
||
progressImpl({ res.rowsInFirstColumn(), res.bytes() });
|
||
pre_reader->fillMissingColumns(res, task->ordered_names, task->should_reorder);
|
||
|
||
/// Вычислим выражение в PREWHERE.
|
||
prewhere_actions->execute(res);
|
||
|
||
ColumnPtr column = res.getByName(prewhere_column).column;
|
||
if (task->remove_prewhere_column)
|
||
res.erase(prewhere_column);
|
||
|
||
const auto pre_bytes = res.bytes();
|
||
|
||
/** Если фильтр - константа (например, написано PREWHERE 1),
|
||
* то либо вернём пустой блок, либо вернём блок без изменений.
|
||
*/
|
||
if (const auto column_const = typeid_cast<const ColumnConstUInt8 *>(column.get()))
|
||
{
|
||
if (!column_const->getData())
|
||
{
|
||
res.clear();
|
||
return res;
|
||
}
|
||
|
||
for (const auto & range : ranges_to_read)
|
||
reader->readRange(range.begin, range.end, res);
|
||
|
||
progressImpl({ 0, res.bytes() - pre_bytes });
|
||
}
|
||
else if (const auto column_vec = typeid_cast<const ColumnUInt8 *>(column.get()))
|
||
{
|
||
size_t index_granularity = storage.index_granularity;
|
||
|
||
const auto & pre_filter = column_vec->getData();
|
||
IColumn::Filter post_filter(pre_filter.size());
|
||
|
||
/// Прочитаем в нужных отрезках остальные столбцы и составим для них свой фильтр.
|
||
size_t pre_filter_pos = 0;
|
||
size_t post_filter_pos = 0;
|
||
|
||
for (const auto & range : ranges_to_read)
|
||
{
|
||
auto begin = range.begin;
|
||
auto pre_filter_begin_pos = pre_filter_pos;
|
||
|
||
for (auto mark = range.begin; mark <= range.end; ++mark)
|
||
{
|
||
UInt8 nonzero = 0;
|
||
|
||
if (mark != range.end)
|
||
{
|
||
const size_t limit = std::min(pre_filter.size(), pre_filter_pos + index_granularity);
|
||
for (size_t row = pre_filter_pos; row < limit; ++row)
|
||
nonzero |= pre_filter[row];
|
||
}
|
||
|
||
if (!nonzero)
|
||
{
|
||
if (mark > begin)
|
||
{
|
||
memcpy(
|
||
&post_filter[post_filter_pos],
|
||
&pre_filter[pre_filter_begin_pos],
|
||
pre_filter_pos - pre_filter_begin_pos);
|
||
post_filter_pos += pre_filter_pos - pre_filter_begin_pos;
|
||
reader->readRange(begin, mark, res);
|
||
}
|
||
begin = mark + 1;
|
||
pre_filter_begin_pos = std::min(pre_filter_pos + index_granularity, pre_filter.size());
|
||
}
|
||
|
||
if (mark < range.end)
|
||
pre_filter_pos = std::min(pre_filter_pos + index_granularity, pre_filter.size());
|
||
}
|
||
}
|
||
|
||
if (!post_filter_pos)
|
||
{
|
||
res.clear();
|
||
continue;
|
||
}
|
||
|
||
progressImpl({ 0, res.bytes() - pre_bytes });
|
||
|
||
post_filter.resize(post_filter_pos);
|
||
|
||
/// Отфильтруем столбцы, относящиеся к PREWHERE, используя pre_filter,
|
||
/// остальные столбцы - используя post_filter.
|
||
size_t rows = 0;
|
||
for (const auto i : ext::range(0, res.columns()))
|
||
{
|
||
auto & col = res.getByPosition(i);
|
||
if (col.name == prewhere_column && res.columns() > 1)
|
||
continue;
|
||
col.column =
|
||
col.column->filter(task->column_name_set.count(col.name) ? post_filter : pre_filter);
|
||
rows = col.column->size();
|
||
}
|
||
|
||
/// Заменим столбец со значением условия из PREWHERE на константу.
|
||
if (!task->remove_prewhere_column)
|
||
res.getByName(prewhere_column).column = new ColumnConstUInt8{rows, 1};
|
||
}
|
||
else
|
||
throw Exception{
|
||
"Illegal type " + column->getName() + " of column for filter. Must be ColumnUInt8 or ColumnConstUInt8.",
|
||
ErrorCodes::ILLEGAL_TYPE_OF_COLUMN_FOR_FILTER
|
||
};
|
||
|
||
reader->fillMissingColumnsAndReorder(res, task->ordered_names);
|
||
}
|
||
while (!task->mark_ranges.empty() && !res && !isCancelled());
|
||
}
|
||
else
|
||
{
|
||
size_t space_left = std::max(1LU, block_size_marks);
|
||
|
||
while (!task->mark_ranges.empty() && space_left && !isCancelled())
|
||
{
|
||
auto & range = task->mark_ranges.back();
|
||
|
||
const size_t marks_to_read = std::min(range.end - range.begin, space_left);
|
||
reader->readRange(range.begin, range.begin + marks_to_read, res);
|
||
|
||
space_left -= marks_to_read;
|
||
range.begin += marks_to_read;
|
||
if (range.begin == range.end)
|
||
task->mark_ranges.pop_back();
|
||
}
|
||
|
||
progressImpl({ res.rowsInFirstColumn(), res.bytes() });
|
||
|
||
reader->fillMissingColumns(res, task->ordered_names, task->should_reorder);
|
||
}
|
||
|
||
return res;
|
||
}
|
||
|
||
void injectVirtualColumns(Block & block)
|
||
{
|
||
const auto rows = block.rowsInFirstColumn();
|
||
|
||
/// add virtual columns
|
||
if (!virt_column_names.empty())
|
||
{
|
||
for (const auto & virt_column_name : virt_column_names)
|
||
{
|
||
if (virt_column_name == "_part")
|
||
{
|
||
block.insert(ColumnWithTypeAndName{
|
||
ColumnConst<String>{rows, task->data_part->name}.convertToFullColumn(),
|
||
new DataTypeString,
|
||
virt_column_name
|
||
});
|
||
}
|
||
else if (virt_column_name == "_part_index")
|
||
{
|
||
block.insert(ColumnWithTypeAndName{
|
||
ColumnConst<UInt64>{rows, task->part_index_in_query}.convertToFullColumn(),
|
||
new DataTypeUInt64,
|
||
virt_column_name
|
||
});
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
MergeTreeReadPoolPtr pool;
|
||
const std::size_t block_size_marks;
|
||
const std::size_t min_marks_to_read;
|
||
MergeTreeData & storage;
|
||
const bool use_uncompressed_cache;
|
||
ExpressionActionsPtr prewhere_actions;
|
||
const String prewhere_column;
|
||
const std::size_t min_bytes_to_use_direct_io;
|
||
const std::size_t max_read_buffer_size;
|
||
const Names virt_column_names;
|
||
|
||
Logger * log;
|
||
|
||
using MergeTreeReaderPtr = std::unique_ptr<MergeTreeReader>;
|
||
|
||
UncompressedCachePtr owned_uncompressed_cache;
|
||
MarkCachePtr owned_mark_cache;
|
||
|
||
MergeTreeReadTaskPtr task;
|
||
MergeTreeReaderPtr reader;
|
||
MergeTreeReaderPtr pre_reader;
|
||
};
|
||
|
||
|
||
}
|