Most likely improve performance

base/common/DateLUTImpl.h

@@ -944,16 +944,70 @@ public:
     }
 
 
+    struct DateComponents
+    {
+        uint16_t year;
+        uint8_t month;
+        uint8_t day;
+    };
+
+    struct TimeComponents
+    {
+        uint8_t hour;
+        uint8_t minute;
+        uint8_t second;
+    };
+
+    struct DateTimeComponents
+    {
+        DateComponents date;
+        TimeComponents time;
+    };
+
+    inline DateComponents toDateComponents(time_t t) const
+    {
+        const Values & values = getValues(t);
+        return { values.year, values.month, values.day_of_month };
+    }
+
+    inline DateTimeComponents toDateTimeComponents(time_t t) const
+    {
+        const LUTIndex index = findIndex(t);
+        const Values & values = lut[index];
+
+        DateTimeComponents res;
+
+        res.date.year = values.year;
+        res.date.month = values.month;
+        res.date.day = values.day_of_month;
+
+        time_t time = t - values.date;
+        if (time >= values.time_at_offset_change())
+            time += values.amount_of_offset_change();
+
+        res.time.second = time % 60;
+        res.time.minute = time / 60 % 60;
+        res.time.hour = time / 3600;
+
+        /// In case time was changed backwards at the start of next day, we will repeat the hour 23.
+        if (unlikely(res.time.hour > 23))
+            res.time.hour = 23;
+
+        return res;
+    }
+
+
     inline UInt64 toNumYYYYMMDDhhmmss(time_t t) const
     {
-        const Values & values = find(t);
+        DateTimeComponents components = toDateTimeComponents(t);
+
         return
-              toSecond(t)
-            + toMinute(t) * 100
-            + toHour(t) * 10000
-            + UInt64(values.day_of_month) * 1000000
-            + UInt64(values.month) * 100000000
-            + UInt64(values.year) * 10000000000;
+              components.time.second
+            + components.time.minute * 100
+            + components.time.hour * 10000
+            + UInt64(components.date.day) * 1000000
+            + UInt64(components.date.month) * 100000000
+            + UInt64(components.date.year) * 10000000000;
     }
 
     inline time_t YYYYMMDDhhmmssToTime(UInt64 num) const
@@ -972,16 +1026,19 @@ public:
 
     inline NO_SANITIZE_UNDEFINED time_t addDays(time_t t, Int64 delta) const
     {
-        LUTIndex index = findIndex(t);
-        time_t time_offset = toHour(t) * 3600 + toMinute(t) * 60 + toSecond(t);
+        const LUTIndex index = findIndex(t);
+        const Values & values = lut[index];
 
-        index += delta;
-        index &= date_lut_mask;
+        time_t time = t - values.date;
+        if (time >= values.time_at_offset_change())
+            time += values.amount_of_offset_change();
 
-        if (time_offset >= lut[index].time_at_offset_change())
-            time_offset -= lut[index].amount_of_offset_change();
+        const LUTIndex new_index = index + delta;
 
-        return lut[index].date + time_offset;
+        if (time >= lut[new_index].time_at_offset_change())
+            time -= lut[new_index].amount_of_offset_change();
+
+        return lut[new_index].date + time;
     }
 
     inline NO_SANITIZE_UNDEFINED time_t addWeeks(time_t t, Int64 delta) const
@@ -1033,12 +1090,17 @@ public:
     {
         const auto result_day = addMonthsIndex(t, delta);
 
-        time_t time_offset = toHour(t) * 3600 + toMinute(t) * 60 + toSecond(t);
+        const LUTIndex index = findIndex(t);
+        const Values & values = lut[index];
+
+        time_t time = t - values.date;
+        if (time >= values.time_at_offset_change())
+            time += values.amount_of_offset_change();
 
-        if (time_offset >= lut[result_day].time_at_offset_change())
-            time_offset -= lut[result_day].amount_of_offset_change();
+        if (time >= lut[result_day].time_at_offset_change())
+            time -= lut[result_day].amount_of_offset_change();
 
-        return lut[result_day].date + time_offset;
+        return lut[result_day].date + time;
     }
 
     inline ExtendedDayNum NO_SANITIZE_UNDEFINED addMonths(ExtendedDayNum d, Int64 delta) const
@@ -1077,12 +1139,17 @@ public:
     {
         auto result_day = addYearsIndex(t, delta);
 
-        time_t time_offset = toHour(t) * 3600 + toMinute(t) * 60 + toSecond(t);
+        const LUTIndex index = findIndex(t);
+        const Values & values = lut[index];
+
+        time_t time = t - values.date;
+        if (time >= values.time_at_offset_change())
+            time += values.amount_of_offset_change();
 
-        if (time_offset >= lut[result_day].time_at_offset_change())
-            time_offset -= lut[result_day].amount_of_offset_change();
+        if (time >= lut[result_day].time_at_offset_change())
+            time -= lut[result_day].amount_of_offset_change();
 
-        return lut[result_day].date + time_offset;
+        return lut[result_day].date + time;
     }
 
     inline ExtendedDayNum addYears(ExtendedDayNum d, Int64 delta) const
@@ -1093,29 +1160,25 @@ public:
 
     inline std::string timeToString(time_t t) const
     {
-        const Values & values = getValues(t);
+        DateTimeComponents components = toDateTimeComponents(t);
 
         std::string s {"0000-00-00 00:00:00"};
 
-        s[0] += values.year / 1000;
-        s[1] += (values.year / 100) % 10;
-        s[2] += (values.year / 10) % 10;
-        s[3] += values.year % 10;
-        s[5] += values.month / 10;
-        s[6] += values.month % 10;
-        s[8] += values.day_of_month / 10;
-        s[9] += values.day_of_month % 10;
-
-        auto hour = toHour(t);
-        auto minute = toMinute(t);
-        auto second = toSecond(t);
-
-        s[11] += hour / 10;
-        s[12] += hour % 10;
-        s[14] += minute / 10;
-        s[15] += minute % 10;
-        s[17] += second / 10;
-        s[18] += second % 10;
+        s[0] += components.date.year / 1000;
+        s[1] += (components.date.year / 100) % 10;
+        s[2] += (components.date.year / 10) % 10;
+        s[3] += components.date.year % 10;
+        s[5] += components.date.month / 10;
+        s[6] += components.date.month % 10;
+        s[8] += components.date.day / 10;
+        s[9] += components.date.day % 10;
+
+        s[11] += components.time.hour / 10;
+        s[12] += components.time.hour % 10;
+        s[14] += components.time.minute / 10;
+        s[15] += components.time.minute % 10;
+        s[17] += components.time.second / 10;
+        s[18] += components.time.second % 10;
 
         return s;
     }

base/common/LocalDate.h

@@ -92,17 +92,6 @@ public:
     LocalDate(const LocalDate &) noexcept = default;
     LocalDate & operator= (const LocalDate &) noexcept = default;
 
-    LocalDate & operator= (time_t time)
-    {
-        init(time);
-        return *this;
-    }
-
-    operator time_t() const
-    {
-        return DateLUT::instance().makeDate(m_year, m_month, m_day);
-    }
-
     DayNum getDayNum() const
     {
         const auto & lut = DateLUT::instance();
@@ -167,12 +156,3 @@ public:
 };
 
 static_assert(sizeof(LocalDate) == 4);
-
-
-namespace std
-{
-inline string to_string(const LocalDate & date)
-{
-    return date.toString();
-}
-}

base/common/LocalDateTime.h

@@ -29,29 +29,16 @@ private:
     /// NOTE We may use attribute packed instead, but it is less portable.
     unsigned char pad = 0;
 
-    void init(time_t time)
+    void init(time_t time, const DateLUTImpl & time_zone)
     {
-        if (unlikely(time > DATE_LUT_MAX || time == 0))
-        {
-            m_year = 0;
-            m_month = 0;
-            m_day = 0;
-            m_hour = 0;
-            m_minute = 0;
-            m_second = 0;
-
-            return;
-        }
-
-        const auto & date_lut = DateLUT::instance();
-        const auto & values = date_lut.getValues(time);
-
-        m_year = values.year;
-        m_month = values.month;
-        m_day = values.day_of_month;
-        m_hour = date_lut.toHour(time);
-        m_minute = date_lut.toMinute(time);
-        m_second = date_lut.toSecond(time);
+        DateLUTImpl::DateTimeComponents components = time_zone.toDateTimeComponents(time);
+
+        m_year = components.date.year;
+        m_month = components.date.month;
+        m_day = components.date.day;
+        m_hour = components.time.hour;
+        m_minute = components.time.minute;
+        m_second = components.time.second;
 
         (void)pad;  /// Suppress unused private field warning.
     }
@@ -73,9 +60,9 @@ private:
     }
 
 public:
-    explicit LocalDateTime(time_t time)
+    explicit LocalDateTime(time_t time, const DateLUTImpl & time_zone = DateLUT::instance())
     {
-        init(time);
+        init(time, time_zone);
     }
 
     LocalDateTime(unsigned short year_, unsigned char month_, unsigned char day_,
@@ -104,19 +91,6 @@ public:
     LocalDateTime(const LocalDateTime &) noexcept = default;
     LocalDateTime & operator= (const LocalDateTime &) noexcept = default;
 
-    LocalDateTime & operator= (time_t time)
-    {
-        init(time);
-        return *this;
-    }
-
-    operator time_t() const
-    {
-        return m_year == 0
-            ? 0
-            : DateLUT::instance().makeDateTime(m_year, m_month, m_day, m_hour, m_minute, m_second);
-    }
-
     unsigned short year() const { return m_year; }
     unsigned char month() const { return m_month; }
     unsigned char day() const { return m_day; }
@@ -167,14 +141,3 @@ public:
 };
 
 static_assert(sizeof(LocalDateTime) == 8);
-
-
-namespace std
-{
-inline string to_string(const LocalDateTime & datetime)
-{
-    stringstream str;
-    str << datetime;
-    return str.str();
-}
-}

programs/git-import/git-import.cpp

@@ -1064,7 +1064,7 @@ void processCommit(
 
     time_t commit_time;
     readText(commit_time, in);
-    commit.time = commit_time;
+    commit.time = LocalDateTime(commit_time);
     assertChar('\0', in);
     readNullTerminated(commit.author, in);
     std::string parent_hash;

src/DataStreams/PostgreSQLBlockInputStream.cpp

@@ -160,8 +160,13 @@ void PostgreSQLBlockInputStream::insertValue(IColumn & column, std::string_view
             assert_cast<ColumnUInt16 &>(column).insertValue(UInt16{LocalDate{std::string(value)}.getDayNum()});
             break;
         case ValueType::vtDateTime:
-            assert_cast<ColumnUInt32 &>(column).insertValue(time_t{LocalDateTime{std::string(value)}});
+        {
+            ReadBufferFromString in(value);
+            time_t time = 0;
+            readDateTimeText(time, in);
+            assert_cast<ColumnUInt32 &>(column).insertValue(time);
             break;
+        }
         case ValueType::vtDateTime64:[[fallthrough]];
         case ValueType::vtDecimal32: [[fallthrough]];
         case ValueType::vtDecimal64: [[fallthrough]];
@@ -257,7 +262,13 @@ void PostgreSQLBlockInputStream::prepareArrayInfo(size_t column_idx, const DataT
     else if (which.isDate())
         parser = [](std::string & field) -> Field { return UInt16{LocalDate{field}.getDayNum()}; };
     else if (which.isDateTime())
-        parser = [](std::string & field) -> Field { return time_t{LocalDateTime{field}}; };
+        parser = [](std::string & field) -> Field
+        {
+            ReadBufferFromString in(field);
+            time_t time = 0;
+            readDateTimeText(time, in);
+            return time;
+        };
     else if (which.isDecimal32())
         parser = [nested](std::string & field) -> Field
         {

src/Dictionaries/ClickHouseDictionarySource.cpp

@@ -118,10 +118,9 @@ std::string ClickHouseDictionarySource::getUpdateFieldAndDate()
 {
     if (update_time != std::chrono::system_clock::from_time_t(0))
     {
-        auto tmp_time = update_time;
+        time_t hr_time = std::chrono::system_clock::to_time_t(update_time) - 1;
+        std::string str_time = DateLUT::instance().timeToString(hr_time);
         update_time = std::chrono::system_clock::now();
-        time_t hr_time = std::chrono::system_clock::to_time_t(tmp_time) - 1;
-        std::string str_time = std::to_string(LocalDateTime(hr_time));
         return query_builder.composeUpdateQuery(update_field, str_time);
     }
     else

src/Dictionaries/MySQLDictionarySource.cpp

@@ -107,10 +107,9 @@ std::string MySQLDictionarySource::getUpdateFieldAndDate()
 {
     if (update_time != std::chrono::system_clock::from_time_t(0))
     {
-        auto tmp_time = update_time;
+        time_t hr_time = std::chrono::system_clock::to_time_t(update_time) - 1;
+        std::string str_time = DateLUT::instance().timeToString(hr_time);
         update_time = std::chrono::system_clock::now();
-        time_t hr_time = std::chrono::system_clock::to_time_t(tmp_time) - 1;
-        std::string str_time = std::to_string(LocalDateTime(hr_time));
         return query_builder.composeUpdateQuery(update_field, str_time);
     }
     else
@@ -262,7 +261,7 @@ LocalDateTime MySQLDictionarySource::getLastModification(mysqlxx::Pool::Entry &
             if (!update_time_value.isNull())
             {
                 modification_time = update_time_value.getDateTime();
-                LOG_TRACE(log, "Got modification time: {}", modification_time);
+                LOG_TRACE(log, "Got modification time: {}", update_time_value.getString());
             }
 
             /// fetch remaining rows to avoid "commands out of sync" error

src/Dictionaries/PostgreSQLDictionarySource.cpp

@@ -127,10 +127,9 @@ std::string PostgreSQLDictionarySource::getUpdateFieldAndDate()
 {
     if (update_time != std::chrono::system_clock::from_time_t(0))
     {
-        auto tmp_time = update_time;
+        time_t hr_time = std::chrono::system_clock::to_time_t(update_time) - 1;
+        std::string str_time = DateLUT::instance().timeToString(hr_time);
         update_time = std::chrono::system_clock::now();
-        time_t hr_time = std::chrono::system_clock::to_time_t(tmp_time) - 1;
-        std::string str_time = std::to_string(LocalDateTime(hr_time));
         return query_builder.composeUpdateQuery(update_field, str_time);
     }
     else

src/Dictionaries/RedisBlockInputStream.cpp

@@ -99,8 +99,13 @@ namespace DB
                     assert_cast<ColumnUInt16 &>(column).insertValue(parse<LocalDate>(string_value).getDayNum());
                     break;
                 case ValueType::vtDateTime:
-                    assert_cast<ColumnUInt32 &>(column).insertValue(static_cast<UInt32>(parse<LocalDateTime>(string_value)));
+                {
+                    ReadBufferFromString in(string_value);
+                    time_t time = 0;
+                    readDateTimeText(time, in);
+                    assert_cast<ColumnUInt32 &>(column).insertValue(time);
                     break;
+                }
                 case ValueType::vtUUID:
                     assert_cast<ColumnUInt128 &>(column).insertValue(parse<UUID>(string_value));
                     break;

src/Dictionaries/XDBCDictionarySource.cpp

@@ -156,10 +156,9 @@ std::string XDBCDictionarySource::getUpdateFieldAndDate()
 {
     if (update_time != std::chrono::system_clock::from_time_t(0))
     {
-        auto tmp_time = update_time;
+        time_t hr_time = std::chrono::system_clock::to_time_t(update_time) - 1;
+        std::string str_time = DateLUT::instance().timeToString(hr_time);
         update_time = std::chrono::system_clock::now();
-        time_t hr_time = std::chrono::system_clock::to_time_t(tmp_time) - 1;
-        std::string str_time = std::to_string(LocalDateTime(hr_time));
         return query_builder.composeUpdateQuery(update_field, str_time);
     }
     else

src/Formats/MySQLBlockInputStream.cpp

@@ -11,6 +11,7 @@
 #    include <Columns/ColumnFixedString.h>
 #    include <DataTypes/IDataType.h>
 #    include <DataTypes/DataTypeNullable.h>
+#    include <IO/ReadBufferFromString.h>
 #    include <IO/ReadHelpers.h>
 #    include <IO/WriteHelpers.h>
 #    include <IO/Operators.h>
@@ -97,8 +98,13 @@ namespace
                 assert_cast<ColumnUInt16 &>(column).insertValue(UInt16(value.getDate().getDayNum()));
                 break;
             case ValueType::vtDateTime:
-                assert_cast<ColumnUInt32 &>(column).insertValue(UInt32(value.getDateTime()));
+            {
+                ReadBufferFromString in(value);
+                time_t time = 0;
+                readDateTimeText(time, in);
+                assert_cast<ColumnUInt32 &>(column).insertValue(time);
                 break;
+            }
             case ValueType::vtUUID:
                 assert_cast<ColumnUInt128 &>(column).insert(parse<UUID>(value.data(), value.size()));
                 break;

src/IO/WriteHelpers.h

@@ -821,24 +821,18 @@ inline void writeDateTimeText(const LocalDateTime & datetime, WriteBuffer & buf)
 template <char date_delimeter = '-', char time_delimeter = ':', char between_date_time_delimiter = ' '>
 inline void writeDateTimeText(time_t datetime, WriteBuffer & buf, const DateLUTImpl & time_zone = DateLUT::instance())
 {
-    const auto & values = time_zone.getValues(datetime);
-    writeDateTimeText<date_delimeter, time_delimeter, between_date_time_delimiter>(
-        LocalDateTime(values.year, values.month, values.day_of_month,
-            time_zone.toHour(datetime), time_zone.toMinute(datetime), time_zone.toSecond(datetime)), buf);
+    writeDateTimeText<date_delimeter, time_delimeter, between_date_time_delimiter>(LocalDateTime(datetime, time_zone), buf);
 }
 
 /// In the format YYYY-MM-DD HH:MM:SS.NNNNNNNNN, according to the specified time zone.
 template <char date_delimeter = '-', char time_delimeter = ':', char between_date_time_delimiter = ' ', char fractional_time_delimiter = '.'>
-inline void writeDateTimeText(DateTime64 datetime64, UInt32 scale, WriteBuffer & buf, const DateLUTImpl & date_lut = DateLUT::instance())
+inline void writeDateTimeText(DateTime64 datetime64, UInt32 scale, WriteBuffer & buf, const DateLUTImpl & time_zone = DateLUT::instance())
 {
     static constexpr UInt32 MaxScale = DecimalUtils::max_precision<DateTime64>;
     scale = scale > MaxScale ? MaxScale : scale;
 
     auto components = DecimalUtils::split(datetime64, scale);
-    const auto & values = date_lut.getValues(components.whole);
-    writeDateTimeText<date_delimeter, time_delimeter, between_date_time_delimiter>(
-        LocalDateTime(values.year, values.month, values.day_of_month,
-            date_lut.toHour(components.whole), date_lut.toMinute(components.whole), date_lut.toSecond(components.whole)), buf);
+    writeDateTimeText<date_delimeter, time_delimeter, between_date_time_delimiter>(LocalDateTime(components.whole, time_zone), buf);
 
     if (scale > 0)
     {

src/Storages/MergeTree/MergeTreeMutationEntry.cpp

@@ -75,7 +75,9 @@ MergeTreeMutationEntry::MergeTreeMutationEntry(DiskPtr disk_, const String & pat
 
     LocalDateTime create_time_dt;
     *buf >> "create time: " >> create_time_dt >> "\n";
-    create_time = create_time_dt;
+    create_time = DateLUT::instance().makeDateTime(
+        create_time_dt.year(), create_time_dt.month(), create_time_dt.day(),
+        create_time_dt.hour(), create_time_dt.minute(), create_time_dt.second());
 
     *buf >> "commands: ";
     commands.readText(*buf);

src/Storages/MergeTree/ReplicatedMergeTreeLogEntry.cpp

@@ -162,7 +162,9 @@ void ReplicatedMergeTreeLogEntryData::readText(ReadBuffer & in)
     {
         LocalDateTime create_time_dt;
         in >> "create_time: " >> create_time_dt >> "\n";
-        create_time = create_time_dt;
+        create_time = DateLUT::instance().makeDateTime(
+            create_time_dt.year(), create_time_dt.month(), create_time_dt.day(),
+            create_time_dt.hour(), create_time_dt.minute(), create_time_dt.second());
     }
 
     in >> "source replica: " >> source_replica >> "\n";

src/Storages/MergeTree/ReplicatedMergeTreeMutationEntry.cpp

@@ -37,7 +37,9 @@ void ReplicatedMergeTreeMutationEntry::readText(ReadBuffer & in)
 
     LocalDateTime create_time_dt;
     in >> "create time: " >> create_time_dt >> "\n";
-    create_time = create_time_dt;
+    create_time = DateLUT::instance().makeDateTime(
+        create_time_dt.year(), create_time_dt.month(), create_time_dt.day(),
+        create_time_dt.hour(), create_time_dt.minute(), create_time_dt.second());
 
     in >> "source replica: " >> source_replica >> "\n";
 

src/Storages/StorageReplicatedMergeTree.cpp

@@ -1450,7 +1450,7 @@ bool StorageReplicatedMergeTree::tryExecuteMerge(const LogEntry & entry)
     {
         LOG_INFO(log, "Will try to fetch part {} until '{}' because this part assigned to recompression merge. "
             "Source replica {} will try to merge this part first", entry.new_part_name,
-            LocalDateTime(entry.create_time + storage_settings_ptr->try_fetch_recompressed_part_timeout.totalSeconds()), entry.source_replica);
+            DateLUT::instance().timeToString(entry.create_time + storage_settings_ptr->try_fetch_recompressed_part_timeout.totalSeconds()), entry.source_replica);
         return false;
     }