[checkmk-commits] Avoid unnecessary string copies.

Module: check_mk Branch: master Commit: 91bc9c0be96eb1137f6bde204edc57adb532e538 URL: http://git.mathias-kettner.de/git/?p=check_mk.git;a=commit;h=91bc9c0be96eb1… Author: Sven Panne &lt;sp(a)mathias-kettner.de&gt; Date: Wed Aug 2 14:13:19 2017 +0200 Avoid unnecessary string copies. The code is a bit more verbose than usual, but parsing the monitoring history is a bit performance-sensitive. Change-Id: I8498651adade98174d81ec011327dc11a449a6c2 --- livestatus/src/LogEntry.cc | 58 ++++++++++++++++++++++++++-------------------- livestatus/src/LogEntry.h | 6 +++-- livestatus/src/TableLog.cc | 2 +- 3 files changed, 38 insertions(+), 28 deletions(-) diff --git a/livestatus/src/LogEntry.cc b/livestatus/src/LogEntry.cc index c59d059..91a58f4 100644 --- a/livestatus/src/LogEntry.cc +++ b/livestatus/src/LogEntry.cc @@ -28,12 +28,14 @@ #include <unordered_map> #include <utility> #include "MonitoringCore.h" -#include "StringUtils.h" -using mk::starts_with; using std::string; using std::unordered_map; +// 0123456789012345678901234567890 +// [1234567890] FOO BAR: blah blah +static constexpr size_t timestamp_prefix_length = 13; + // TODO(sp) Fix classifyLogMessage() below to always set all fields and remove // this set-me-to-zero-to-be-sure-block. LogEntry::LogEntry(MonitoringCore *mc, unsigned lineno, string line) @@ -54,9 +56,6 @@ LogEntry::LogEntry(MonitoringCore *mc, unsigned lineno, string line) } _options = &_complete[pos]; - // 0123456789012345678901234567890 - // [1234567890] FOO BAR: blah blah - constexpr size_t timestamp_prefix_length = 13; try { if (_complete.size() < timestamp_prefix_length || _complete[0] != '[' || _complete[11] != ']' || _complete[12] != ' ') { @@ -69,7 +68,7 @@ LogEntry::LogEntry(MonitoringCore *mc, unsigned lineno, string line) return; // ignore invalid lines silently } - classifyLogMessage(&_complete[timestamp_prefix_length]); + classifyLogMessage(); applyWorkarounds(); updateReferences(mc); } @@ -263,51 +262,52 @@ std::vector<LogEntry::LogDef> LogEntry::log_definitions // NOLINT //////////////// LogDef{"EXTERNAL COMMAND", Class::ext_command, LogEntryType::none, {}}}; -void LogEntry::classifyLogMessage(const string &text) { +// A bit verbose, but we avoid unnecessary string copies below. +void LogEntry::classifyLogMessage() { for (const auto &def : log_definitions) { - if (starts_with(text, def.prefix) && - text.compare(def.prefix.size(), 2, ": ") == 0) { - _text = def.prefix; + if (textStartsWith(def.prefix) && + _complete.compare(timestamp_prefix_length + def.prefix.size(), 2, + ": ") == 0) { + _text = &def.prefix[0]; _logclass = def.log_class; _type = def.log_type; // TODO(sp) Use boost::tokenizer instead of this index fiddling - size_t pos = def.prefix.size() + 2; + size_t pos = timestamp_prefix_length + def.prefix.size() + 2; for (Param par : def.params) { - size_t sep_pos = text.find(';', pos); + size_t sep_pos = _complete.find(';', pos); size_t end_pos = - sep_pos == string::npos ? text.size() : sep_pos; - assign(par, text.substr(pos, end_pos - pos)); - pos = sep_pos == string::npos ? text.size() : (sep_pos + 1); + sep_pos == string::npos ? _complete.size() : sep_pos; + assign(par, _complete.substr(pos, end_pos - pos)); + pos = + sep_pos == string::npos ? _complete.size() : (sep_pos + 1); } return; } } - _text = text; - if (starts_with(text, "LOG VERSION: 2.0")) { + _text = &_complete[timestamp_prefix_length]; + if (textStartsWith("LOG VERSION: 2.0")) { _logclass = Class::program; _type = LogEntryType::log_version; return; } - if (starts_with(text, "logging initial states") || - starts_with(text, "logging intitial states")) { + if (textStartsWith("logging initial states") || + textStartsWith("logging intitial states")) { _logclass = Class::program; _type = LogEntryType::log_initial_states; return; } - if (text.find("starting...") != string::npos || - text.find("active mode...") != string::npos) { + if (textContains("starting...") || textContains("active mode...")) { _logclass = Class::program; _type = LogEntryType::core_starting; return; } - if (text.find("shutting down...") != string::npos || - text.find("Bailing out") != string::npos || - text.find("standby mode...") != string::npos) { + if (textContains("shutting down...") || textContains("Bailing out") || + textContains("standby mode...")) { _logclass = Class::program; _type = LogEntryType::core_stopping; return; } - if (text.find("restarting...") != string::npos) { + if (textContains("restarting...")) { _logclass = Class::program; _type = LogEntryType::none; return; @@ -316,6 +316,14 @@ void LogEntry::classifyLogMessage(const string &text) { _type = LogEntryType::none; } +bool LogEntry::textStartsWith(const string &what) { + return _complete.compare(timestamp_prefix_length, what.size(), what) == 0; +} + +bool LogEntry::textContains(const string &what) { + return _complete.find(what, timestamp_prefix_length) != string::npos; +} + // The NotifyHelper class has a long, tragic history: Through a long series of // commits, it suffered from spelling mistakes like "HOST_NOTIFICATION" or "HOST // NOTIFICATION" (without a colon), parameter lists not matching the diff --git a/livestatus/src/LogEntry.h b/livestatus/src/LogEntry.h index f45f23d..f24267e 100644 --- a/livestatus/src/LogEntry.h +++ b/livestatus/src/LogEntry.h @@ -82,7 +82,7 @@ public: LogEntryType _type; std::string _complete; // copy of complete unsplit message const char *_options; // points into _complete after ':' - std::string _text; + const char *_text; // points into _complete or into static data std::string _host_name; std::string _svc_desc; std::string _command_name; @@ -130,7 +130,9 @@ private: bool assign(Param par, const std::string &field); void applyWorkarounds(); - void classifyLogMessage(const std::string &text); + void classifyLogMessage(); + bool textStartsWith(const std::string &what); + bool textContains(const std::string &what); }; #endif // LogEntry_h diff --git a/livestatus/src/TableLog.cc b/livestatus/src/TableLog.cc index 1f55496..bf320a3 100644 --- a/livestatus/src/TableLog.cc +++ b/livestatus/src/TableLog.cc @@ -71,7 +71,7 @@ TableLog::TableLog(MonitoringCore *mc, LogCache *log_cache) addColumn(make_unique<OffsetSStringColumn>( "message", "The complete message line including the timestamp", DANGEROUS_OFFSETOF(LogEntry, _complete), -1, -1, -1)); - addColumn(make_unique<OffsetSStringColumn>( + addColumn(make_unique<OffsetStringColumn>( "type", "The type of the message (text before the colon), the message itself for info messages", DANGEROUS_OFFSETOF(LogEntry, _text), -1, -1, -1));