code/Debug/Model/Logging.php
public function getTotalLineCount()
    {
        if ($this->logLineCount === null) {
            $this->logLineCount = 0;
            foreach ($this->getFiles() as $log) {
                $this->logLineCount += $this->getLineCount($log);
            }
        }

        return $this->logLineCount;
    }
public function getTotalLineCount()
    {
        if ($this->logLineCount === null) {
            $this->logLineCount = 0;
            foreach ($this->getFiles() as $log) {
                $this->logLineCount += $this->getLineCount($log);
            }
        }

        return $this->logLineCount;
    }
Returns number of log lines added in all of registered logs

@return int