mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-09-30 05:30:51 +00:00
Merge branch 'master' of github.com:ClickHouse/ClickHouse into disk-async-read
This commit is contained in:
commit
5e63ec4489
@ -317,7 +317,7 @@ class ReverseIndex
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{
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public:
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ReverseIndex(UInt64 num_prefix_rows_to_skip_, UInt64 base_index_)
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: num_prefix_rows_to_skip(num_prefix_rows_to_skip_), base_index(base_index_), saved_hash_ptr(nullptr) {}
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: num_prefix_rows_to_skip(num_prefix_rows_to_skip_), base_index(base_index_), external_saved_hash_ptr(nullptr) {}
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void setColumn(ColumnType * column_);
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@ -352,14 +352,14 @@ public:
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if (!use_saved_hash)
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return nullptr;
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UInt64 * ptr = saved_hash_ptr.load();
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UInt64 * ptr = external_saved_hash_ptr.load();
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if (!ptr)
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{
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auto hash = calcHashes();
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ptr = &hash->getData()[0];
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UInt64 * expected = nullptr;
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if (saved_hash_ptr.compare_exchange_strong(expected, ptr))
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saved_hash = std::move(hash);
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if (external_saved_hash_ptr.compare_exchange_strong(expected, ptr))
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external_saved_hash = std::move(hash);
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else
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ptr = expected;
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}
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@ -379,7 +379,9 @@ private:
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/// Lazy initialized.
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std::unique_ptr<IndexMapType> index;
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mutable ColumnUInt64::MutablePtr saved_hash;
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mutable std::atomic<UInt64 *> saved_hash_ptr;
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/// For usage during GROUP BY
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mutable ColumnUInt64::MutablePtr external_saved_hash;
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mutable std::atomic<UInt64 *> external_saved_hash_ptr;
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void buildIndex();
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|
@ -30,7 +30,6 @@ void CachedCompressedReadBuffer::initInput()
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bool CachedCompressedReadBuffer::nextImpl()
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{
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/// Let's check for the presence of a decompressed block in the cache, grab the ownership of this block, if it exists.
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UInt128 key = cache->hash(path, file_pos);
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@ -60,6 +59,13 @@ bool CachedCompressedReadBuffer::nextImpl()
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working_buffer = Buffer(owned_cell->data.data(), owned_cell->data.data() + owned_cell->data.size() - owned_cell->additional_bytes);
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/// nextimpl_working_buffer_offset is set in the seek function (lazy seek). So we have to
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/// check that we are not seeking beyond working buffer.
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if (nextimpl_working_buffer_offset > working_buffer.size())
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throw Exception("Seek position is beyond the decompressed block"
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" (pos: " + toString(nextimpl_working_buffer_offset) + ", block size: " + toString(working_buffer.size()) + ")",
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ErrorCodes::SEEK_POSITION_OUT_OF_BOUND);
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file_pos += owned_cell->compressed_size;
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return true;
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@ -74,28 +80,29 @@ CachedCompressedReadBuffer::CachedCompressedReadBuffer(
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void CachedCompressedReadBuffer::seek(size_t offset_in_compressed_file, size_t offset_in_decompressed_block)
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{
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/// Nothing to do if we already at required position
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if (file_pos == offset_in_compressed_file
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&& (offset() == offset_in_decompressed_block ||
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nextimpl_working_buffer_offset == offset_in_decompressed_block))
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return;
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if (owned_cell &&
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offset_in_compressed_file == file_pos - owned_cell->compressed_size &&
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offset_in_decompressed_block <= working_buffer.size())
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{
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bytes += offset();
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pos = working_buffer.begin() + offset_in_decompressed_block;
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bytes -= offset();
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}
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else
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{
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/// Remember position in compressed file (will be moved in nextImpl)
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file_pos = offset_in_compressed_file;
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/// We will discard our working_buffer, but have to account rest bytes
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bytes += offset();
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nextImpl();
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if (offset_in_decompressed_block > working_buffer.size())
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throw Exception("Seek position is beyond the decompressed block"
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" (pos: " + toString(offset_in_decompressed_block) + ", block size: " + toString(working_buffer.size()) + ")",
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ErrorCodes::SEEK_POSITION_OUT_OF_BOUND);
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pos = working_buffer.begin() + offset_in_decompressed_block;
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bytes -= offset();
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/// No data, everything discarded
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pos = working_buffer.end();
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/// Remember required offset in decompressed block which will be set in
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/// the next ReadBuffer::next() call
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nextimpl_working_buffer_offset = offset_in_decompressed_block;
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}
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}
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|
@ -15,7 +15,7 @@ namespace DB
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* The external cache is passed as an argument to the constructor.
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* Allows you to increase performance in cases where the same blocks are often read.
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* Disadvantages:
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* - in case you need to read a lot of data in a row, but of them only a part is cached, you have to do seek-and.
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* - in case you need to read a lot of data in a row, but some of them only a part is cached, you have to do seek-and.
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*/
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class CachedCompressedReadBuffer : public CompressedReadBufferBase, public ReadBuffer
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{
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@ -25,6 +25,8 @@ private:
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std::unique_ptr<ReadBufferFromFileBase> file_in;
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const std::string path;
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/// Current position in file_in
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size_t file_pos;
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/// A piece of data from the cache, or a piece of read data that we put into the cache.
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@ -37,9 +39,15 @@ private:
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ReadBufferFromFileBase::ProfileCallback profile_callback;
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clockid_t clock_type {};
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/// Check comment in CompressedReadBuffer
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/* size_t nextimpl_working_buffer_offset; */
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public:
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CachedCompressedReadBuffer(const std::string & path, std::function<std::unique_ptr<ReadBufferFromFileBase>()> file_in_creator, UncompressedCache * cache_, bool allow_different_codecs_ = false);
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/// Seek is lazy. It doesn't move the position anywhere, just remember them and perform actual
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/// seek inside nextImpl.
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void seek(size_t offset_in_compressed_file, size_t offset_in_decompressed_block);
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void setProfileCallback(const ReadBufferFromFileBase::ProfileCallback & profile_callback_, clockid_t clock_type_ = CLOCK_MONOTONIC_COARSE)
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|
@ -33,6 +33,13 @@ bool CompressedReadBufferFromFile::nextImpl()
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decompress(working_buffer, size_decompressed, size_compressed_without_checksum);
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/// nextimpl_working_buffer_offset is set in the seek function (lazy seek). So we have to
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/// check that we are not seeking beyond working buffer.
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if (nextimpl_working_buffer_offset > working_buffer.size())
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throw Exception("Required to move position beyond the decompressed block"
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" (pos: " + toString(nextimpl_working_buffer_offset) + ", block size: " + toString(working_buffer.size()) + ")",
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ErrorCodes::SEEK_POSITION_OUT_OF_BOUND);
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return true;
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}
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@ -67,33 +74,34 @@ CompressedReadBufferFromFile::CompressedReadBufferFromFile(
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void CompressedReadBufferFromFile::seek(size_t offset_in_compressed_file, size_t offset_in_decompressed_block)
|
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{
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/// Nothing to do if we already at required position
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if (!size_compressed && static_cast<size_t>(file_in.getPosition()) == offset_in_compressed_file && /// correct position in compressed file
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(offset() == offset_in_decompressed_block /// correct position in buffer or
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|| nextimpl_working_buffer_offset == offset_in_decompressed_block)) /// we will move our position to correct one
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||||
return;
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/// Our seek is within working_buffer, so just move the position
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if (size_compressed &&
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offset_in_compressed_file == file_in.getPosition() - size_compressed &&
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offset_in_decompressed_block <= working_buffer.size())
|
||||
{
|
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bytes += offset();
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pos = working_buffer.begin() + offset_in_decompressed_block;
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/// `bytes` can overflow and get negative, but in `count()` everything will overflow back and get right.
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bytes -= offset();
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}
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else
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else /// Our seek outside working buffer, so perform "lazy seek"
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{
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/// Actually seek compressed file
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file_in.seek(offset_in_compressed_file, SEEK_SET);
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/// We will discard our working_buffer, but have to account rest bytes
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bytes += offset();
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||||
nextImpl();
|
||||
|
||||
if (offset_in_decompressed_block > working_buffer.size())
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throw Exception("Seek position is beyond the decompressed block"
|
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" (pos: " + toString(offset_in_decompressed_block) + ", block size: " + toString(working_buffer.size()) + ")",
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||||
ErrorCodes::SEEK_POSITION_OUT_OF_BOUND);
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pos = working_buffer.begin() + offset_in_decompressed_block;
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bytes -= offset();
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/// No data, everything discarded
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pos = working_buffer.end();
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size_compressed = 0;
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/// Remember required offset in decompressed block which will be set in
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/// the next ReadBuffer::next() call
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nextimpl_working_buffer_offset = offset_in_decompressed_block;
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}
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}
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size_t CompressedReadBufferFromFile::readBig(char * to, size_t n)
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{
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size_t bytes_read = 0;
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@ -115,9 +123,11 @@ size_t CompressedReadBufferFromFile::readBig(char * to, size_t n)
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auto additional_size_at_the_end_of_buffer = codec->getAdditionalSizeAtTheEndOfBuffer();
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/// If the decompressed block fits entirely where it needs to be copied.
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if (size_decompressed + additional_size_at_the_end_of_buffer <= n - bytes_read)
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/// If the decompressed block fits entirely where it needs to be copied and we don't
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/// need to skip some bytes in decompressed data (seek happened before readBig call).
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if (nextimpl_working_buffer_offset == 0 && size_decompressed + additional_size_at_the_end_of_buffer <= n - bytes_read)
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{
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decompressTo(to + bytes_read, size_decompressed, size_compressed_without_checksum);
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bytes_read += size_decompressed;
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bytes += size_decompressed;
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@ -134,7 +144,11 @@ size_t CompressedReadBufferFromFile::readBig(char * to, size_t n)
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working_buffer = Buffer(memory.data(), &memory[size_decompressed]);
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decompress(working_buffer, size_decompressed, size_compressed_without_checksum);
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pos = working_buffer.begin();
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/// Manually take nextimpl_working_buffer_offset into account, because we don't use
|
||||
/// nextImpl in this method.
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pos = working_buffer.begin() + nextimpl_working_buffer_offset;
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nextimpl_working_buffer_offset = 0;
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bytes_read += read(to + bytes_read, n - bytes_read);
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break;
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|
@ -28,6 +28,19 @@ private:
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ReadBufferFromFileBase & file_in;
|
||||
size_t size_compressed = 0;
|
||||
|
||||
/// This field inherited from ReadBuffer. It's used to perform "lazy" seek, so in seek() call we:
|
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/// 1) actually seek only underlying compressed file_in to offset_in_compressed_file;
|
||||
/// 2) reset current working_buffer;
|
||||
/// 3) remember the position in decompressed block in nextimpl_working_buffer_offset.
|
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/// After following ReadBuffer::next() -> nextImpl call we will read new data into working_buffer and
|
||||
/// ReadBuffer::next() will move our position in the fresh working_buffer to nextimpl_working_buffer_offset and
|
||||
/// reset it to zero.
|
||||
///
|
||||
/// NOTE: We have independent readBig implementation, so we have to take
|
||||
/// nextimpl_working_buffer_offset into account there as well.
|
||||
///
|
||||
/* size_t nextimpl_working_buffer_offset; */
|
||||
|
||||
bool nextImpl() override;
|
||||
void prefetch() override;
|
||||
|
||||
@ -37,6 +50,9 @@ public:
|
||||
CompressedReadBufferFromFile(
|
||||
const std::string & path, const ReadSettings & settings, size_t estimated_size, bool allow_different_codecs_ = false);
|
||||
|
||||
/// Seek is lazy in some sense. We move position in compressed file_in to offset_in_compressed_file, but don't
|
||||
/// read data into working_buffer and don't shit our position to offset_in_decompressed_block. Instead
|
||||
/// we store this offset inside nextimpl_working_buffer_offset.
|
||||
void seek(size_t offset_in_compressed_file, size_t offset_in_decompressed_block);
|
||||
|
||||
size_t readBig(char * to, size_t n) override;
|
||||
|
@ -2,7 +2,6 @@
|
||||
|
||||
#include <Common/Stopwatch.h>
|
||||
#include <IO/ThreadPoolRemoteFSReader.h>
|
||||
#include <common/logger_useful.h>
|
||||
|
||||
|
||||
namespace CurrentMetrics
|
||||
|
@ -12,7 +12,6 @@
|
||||
|
||||
#include <future>
|
||||
#include <iostream>
|
||||
#include <common/logger_useful.h>
|
||||
|
||||
|
||||
namespace ProfileEvents
|
||||
|
@ -75,6 +75,7 @@ size_t MergeTreeReaderWide::readRows(size_t from_mark, bool continue_reading, si
|
||||
OffsetColumns offset_columns;
|
||||
std::unordered_map<String, ISerialization::SubstreamsCache> caches;
|
||||
|
||||
std::unordered_set<std::string> prefetched_streams;
|
||||
if (disk->isRemote() ? settings.read_settings.remote_fs_prefetch : settings.read_settings.local_fs_prefetch)
|
||||
{
|
||||
/// Request reading of data in advance,
|
||||
@ -86,7 +87,7 @@ size_t MergeTreeReaderWide::readRows(size_t from_mark, bool continue_reading, si
|
||||
try
|
||||
{
|
||||
auto & cache = caches[column_from_part.getNameInStorage()];
|
||||
prefetch(column_from_part, from_mark, continue_reading, cache);
|
||||
prefetch(column_from_part, from_mark, continue_reading, cache, prefetched_streams);
|
||||
}
|
||||
catch (Exception & e)
|
||||
{
|
||||
@ -98,6 +99,7 @@ size_t MergeTreeReaderWide::readRows(size_t from_mark, bool continue_reading, si
|
||||
}
|
||||
|
||||
auto name_and_type = columns.begin();
|
||||
|
||||
for (size_t pos = 0; pos < num_columns; ++pos, ++name_and_type)
|
||||
{
|
||||
auto column_from_part = getColumnFromPart(*name_and_type);
|
||||
@ -114,7 +116,9 @@ size_t MergeTreeReaderWide::readRows(size_t from_mark, bool continue_reading, si
|
||||
size_t column_size_before_reading = column->size();
|
||||
auto & cache = caches[column_from_part.getNameInStorage()];
|
||||
|
||||
readData(column_from_part, column, from_mark, continue_reading, max_rows_to_read, cache);
|
||||
readData(
|
||||
column_from_part, column, from_mark, continue_reading,
|
||||
max_rows_to_read, cache, /* was_prefetched =*/ !prefetched_streams.empty());
|
||||
|
||||
/// For elements of Nested, column_size_before_reading may be greater than column size
|
||||
/// if offsets are not empty and were already read, but elements are empty.
|
||||
@ -190,11 +194,11 @@ void MergeTreeReaderWide::addStreams(const NameAndTypePair & name_and_type,
|
||||
|
||||
|
||||
static ReadBuffer * getStream(
|
||||
bool stream_for_prefix,
|
||||
bool seek_to_start,
|
||||
const ISerialization::SubstreamPath & substream_path,
|
||||
MergeTreeReaderWide::FileStreams & streams,
|
||||
const NameAndTypePair & name_and_type,
|
||||
size_t from_mark, bool continue_reading,
|
||||
size_t from_mark, bool seek_to_mark,
|
||||
ISerialization::SubstreamsCache & cache)
|
||||
{
|
||||
/// If substream have already been read.
|
||||
@ -209,9 +213,9 @@ static ReadBuffer * getStream(
|
||||
|
||||
MergeTreeReaderStream & stream = *it->second;
|
||||
|
||||
if (stream_for_prefix)
|
||||
if (seek_to_start)
|
||||
stream.seekToStart();
|
||||
else if (!continue_reading)
|
||||
else if (seek_to_mark)
|
||||
stream.seekToMark(from_mark);
|
||||
|
||||
return stream.data_buffer;
|
||||
@ -222,15 +226,24 @@ void MergeTreeReaderWide::prefetch(
|
||||
const NameAndTypePair & name_and_type,
|
||||
size_t from_mark,
|
||||
bool continue_reading,
|
||||
ISerialization::SubstreamsCache & cache)
|
||||
ISerialization::SubstreamsCache & cache,
|
||||
std::unordered_set<std::string> & prefetched_streams)
|
||||
{
|
||||
const auto & name = name_and_type.name;
|
||||
auto & serialization = serializations[name];
|
||||
|
||||
serialization->enumerateStreams([&](const ISerialization::SubstreamPath & substream_path)
|
||||
{
|
||||
if (ReadBuffer * buf = getStream(false, substream_path, streams, name_and_type, from_mark, continue_reading, cache))
|
||||
buf->prefetch();
|
||||
String stream_name = ISerialization::getFileNameForStream(name_and_type, substream_path);
|
||||
|
||||
if (!prefetched_streams.count(stream_name))
|
||||
{
|
||||
bool seek_to_mark = !continue_reading;
|
||||
if (ReadBuffer * buf = getStream(false, substream_path, streams, name_and_type, from_mark, seek_to_mark, cache))
|
||||
buf->prefetch();
|
||||
|
||||
prefetched_streams.insert(stream_name);
|
||||
}
|
||||
});
|
||||
}
|
||||
|
||||
@ -238,7 +251,7 @@ void MergeTreeReaderWide::prefetch(
|
||||
void MergeTreeReaderWide::readData(
|
||||
const NameAndTypePair & name_and_type, ColumnPtr & column,
|
||||
size_t from_mark, bool continue_reading, size_t max_rows_to_read,
|
||||
ISerialization::SubstreamsCache & cache)
|
||||
ISerialization::SubstreamsCache & cache, bool was_prefetched)
|
||||
{
|
||||
double & avg_value_size_hint = avg_value_size_hints[name_and_type.name];
|
||||
ISerialization::DeserializeBinaryBulkSettings deserialize_settings;
|
||||
@ -251,14 +264,18 @@ void MergeTreeReaderWide::readData(
|
||||
{
|
||||
deserialize_settings.getter = [&](const ISerialization::SubstreamPath & substream_path)
|
||||
{
|
||||
return getStream(true, substream_path, streams, name_and_type, from_mark, continue_reading, cache);
|
||||
return getStream(/* seek_to_start = */true, substream_path, streams, name_and_type, from_mark, /* seek_to_mark = */false, cache);
|
||||
};
|
||||
serialization->deserializeBinaryBulkStatePrefix(deserialize_settings, deserialize_binary_bulk_state_map[name]);
|
||||
}
|
||||
|
||||
deserialize_settings.getter = [&](const ISerialization::SubstreamPath & substream_path)
|
||||
{
|
||||
return getStream(false, substream_path, streams, name_and_type, from_mark, continue_reading, cache);
|
||||
bool seek_to_mark = !was_prefetched && !continue_reading;
|
||||
|
||||
return getStream(
|
||||
/* seek_to_start = */false, substream_path, streams, name_and_type, from_mark,
|
||||
seek_to_mark, cache);
|
||||
};
|
||||
deserialize_settings.continuous_reading = continue_reading;
|
||||
auto & deserialize_state = deserialize_binary_bulk_state_map[name];
|
||||
|
@ -46,14 +46,15 @@ private:
|
||||
void readData(
|
||||
const NameAndTypePair & name_and_type, ColumnPtr & column,
|
||||
size_t from_mark, bool continue_reading, size_t max_rows_to_read,
|
||||
ISerialization::SubstreamsCache & cache);
|
||||
ISerialization::SubstreamsCache & cache, bool was_prefetched);
|
||||
|
||||
/// Make next readData more simple by calling 'prefetch' of all related ReadBuffers.
|
||||
/// Make next readData more simple by calling 'prefetch' of all related ReadBuffers (column streams).
|
||||
void prefetch(
|
||||
const NameAndTypePair & name_and_type,
|
||||
size_t from_mark,
|
||||
bool continue_reading,
|
||||
ISerialization::SubstreamsCache & cache);
|
||||
ISerialization::SubstreamsCache & cache,
|
||||
std::unordered_set<std::string> & prefetched_streams); /// if stream was already prefetched do nothing
|
||||
};
|
||||
|
||||
}
|
||||
|
23
tests/queries/0_stateless/02046_low_cardinality_parallel_group_by.sh
Executable file
23
tests/queries/0_stateless/02046_low_cardinality_parallel_group_by.sh
Executable file
@ -0,0 +1,23 @@
|
||||
#!/usr/bin/env bash
|
||||
# Tags: long
|
||||
|
||||
CURDIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
|
||||
# shellcheck source=../shell_config.sh
|
||||
. "$CURDIR"/../shell_config.sh
|
||||
|
||||
# This is the regression test for parallel usage of LowCardinality column
|
||||
# via Buffer engine.
|
||||
#
|
||||
# See also:
|
||||
# - https://github.com/ClickHouse/ClickHouse/issues/24158
|
||||
# - https://github.com/ClickHouse/ClickHouse/pull/3138
|
||||
|
||||
$CLICKHOUSE_CLIENT -q "DROP TABLE IF EXISTS low_card_buffer_test"
|
||||
$CLICKHOUSE_CLIENT -q "CREATE TABLE low_card_buffer_test (test_text LowCardinality(String)) ENGINE=Buffer('', '', 16, 60, 360, 100, 1000, 10000, 100000)"
|
||||
|
||||
$CLICKHOUSE_BENCHMARK -d 0 -i 1000 -c 5 <<<"SELECT count() FROM low_card_buffer_test GROUP BY test_text format Null" 2>/dev/null &
|
||||
$CLICKHOUSE_BENCHMARK -d 0 -i 1000 -c 2 <<<"INSERT INTO low_card_buffer_test values('TEST1')" 2>/dev/null &
|
||||
wait
|
||||
|
||||
# server is alive
|
||||
$CLICKHOUSE_CLIENT -q "SELECT 1 FORMAT Null"
|
Loading…
Reference in New Issue
Block a user