ColumnSparse: use varint for offsets

This commit is contained in:
Anton Popov 2021-05-12 04:36:47 +03:00
parent a842a599c4
commit e1e1435b00
2 changed files with 6 additions and 5 deletions

View File

@ -6,6 +6,7 @@
#include <Common/assert_cast.h>
#include <IO/ReadHelpers.h>
#include <IO/WriteHelpers.h>
#include <IO/VarInt.h>
namespace DB
{
@ -13,7 +14,7 @@ namespace DB
namespace
{
static constexpr auto END_OF_GRANULE_FLAG = 1ULL << 63;
static constexpr auto END_OF_GRANULE_FLAG = 1ULL << 62;
struct DeserializeStateSparse : public ISerialization::DeserializeBinaryBulkState
{
@ -34,13 +35,13 @@ void serializeOffsets(const IColumn::Offsets & offsets, WriteBuffer & ostr, size
for (size_t i = 0; i < size; ++i)
{
size_t group_size = offsets[i] - start;
writeIntBinary(group_size, ostr);
writeVarUInt(group_size, ostr);
start += group_size + 1;
}
size_t group_size = start < end ? end - start : 0;
group_size |= END_OF_GRANULE_FLAG;
writeIntBinary(group_size, ostr);
writeVarUInt(group_size, ostr);
}
size_t deserializeOffsets(IColumn::Offsets & offsets,
@ -70,7 +71,7 @@ size_t deserializeOffsets(IColumn::Offsets & offsets,
size_t group_size;
while (!istr.eof())
{
readIntBinary(group_size, istr);
readVarUInt(group_size, istr);
bool end_of_granule = group_size & END_OF_GRANULE_FLAG;
group_size &= ~END_OF_GRANULE_FLAG;

View File

@ -33,7 +33,7 @@ struct Settings;
M(UInt64, min_rows_for_compact_part, 0, "Experimental. Minimal number of rows to create part in compact format instead of saving it in RAM", 0) \
M(Bool, in_memory_parts_enable_wal, true, "Whether to write blocks in Native format to write-ahead-log before creation in-memory part", 0) \
M(UInt64, write_ahead_log_max_bytes, 1024 * 1024 * 1024, "Rotate WAL, if it exceeds that amount of bytes", 0) \
M(Float, ratio_for_sparse_serialization, 0, "", 0) \
M(Float, ratio_for_sparse_serialization, 1.1, "", 0) \
\
/** Merge settings. */ \
M(UInt64, merge_max_block_size, DEFAULT_MERGE_BLOCK_SIZE, "How many rows in blocks should be formed for merge operations.", 0) \