laipower/wp-content/plugins/w3-total-cache/UsageStatistics_Source_DbQueriesLog.php

154 lines
3.4 KiB
PHP

<?php
namespace W3TC;
/**
* database queries debug log reader - provides data from this logfile
*/
class UsageStatistics_Source_DbQueriesLog {
// running values
private $timestamp_start;
private $sort_column;
private $by_query = array();
/* if need to read more access log chunks */
private $more_log_needed = true;
function __construct( $timestamp_start, $sort_column ) {
$this->timestamp_start = $timestamp_start;
$this->sort_column = $sort_column;
}
/**
* Lists entries from log
**/
public function list_entries() {
$log_filename = Util_Debug::log_filename( 'dbcache-queries' );
$h = @fopen( $log_filename, 'rb' );
if ( !$h ) {
throw new \Exception( 'Failed to open log file' . $log_filename );
}
fseek( $h, 0, SEEK_END );
$pos = ftell( $h );
$unparsed_head = '';
while ( $pos >= 0 && $this->more_log_needed ) {
$pos -= 8192;
if ( $pos <= 0 ) {
$pos = 0;
}
fseek( $h, $pos );
$s = fread( $h, 8192 );
$unparsed_head = $this->parse_string( $s . $unparsed_head, $pos > 0 );
if ( $pos <= 0 ) {
$this->more_log_needed = false;
}
}
$output = array();
foreach ( $this->by_query as $query => $data ) {
$output[] = array(
'query' => $query,
'count_total' => $data['count_total'],
'count_hit' => $data['count_hit'],
'avg_size' => (int)( $data['sum_size'] / $data['count_total'] ),
'avg_time_ms' => (int)( $data['sum_time_ms'] / $data['count_total'] ),
'sum_time_ms' => (int)$data['sum_time_ms'],
'reasons' => $data['reasons']
);
}
usort( $output, function($a, $b) {
return (int)($b[$this->sort_column]) - (int)($a[$this->sort_column]);
});
$output = array_slice( $output, 0, 200 );
return $output;
}
private function parse_string( $s, $skip_first_line ) {
$s_length = strlen( $s );
$unparsed_head = '';
$n = 0;
if ( $skip_first_line ) {
for ( ; $n < $s_length; $n++ ) {
$c = substr( $s, $n, 1 );
if ( $c == "\r" || $c == "\n" ) {
$unparsed_head = substr( $s, 0, $n + 1 );
break;
}
}
}
$line_start = $n;
for ( ; $n < $s_length; $n++ ) {
$c = substr( $s, $n, 1 );
if ( $c == "\r" || $c == "\n" ) {
if ( $n > $line_start ) {
$this->push_line( substr( $s, $line_start, $n - $line_start ) );
}
$line_start = $n + 1;
}
}
return $unparsed_head;
}
private function push_line( $line ) {
$matches = str_getcsv( $line, "\t" );
if ( !$matches ) {
return;
}
$date_string = $matches[0];
$query = $matches[2];
$time_taken_ms = isset( $matches[3] ) ? (float)$matches[3] / 1000 : 0;
$reason = isset( $matches[4] ) ? $matches[4] : '';
$hit = isset( $matches[5] ) ? $matches[5] : false;
$size = isset( $matches[6] ) ? $matches[6] : 0;
$time = strtotime($date_string);
// dont read more if we touched entries before timeperiod of collection
if ( $time < $this->timestamp_start ) {
$this->more_log_needed = false;
}
if ( !isset( $this->by_query[$query] ) ) {
$this->by_query[$query] = array(
'count_total' => 0,
'count_hit' => 0,
'sum_size' => 0,
'sum_time_ms' => 0,
'reasons' => array()
);
}
$this->by_query[$query]['count_total']++;
if ($hit) {
$this->by_query[$query]['count_hit']++;
}
$this->by_query[$query]['sum_size'] += $size;
$this->by_query[$query]['sum_time_ms'] += $time_taken_ms;
if ( !in_array( $reason, $this->by_query[$query]['reasons']) ) {
$this->by_query[$query]['reasons'][] = $reason;
}
}
}