sqlite-object-cache / includes / lib / class-sqlite-object-cache-statistics.php

class-sqlite-object-cache-statistics.php in SQLite Object Cache 1.0.0, at includes/lib/class-sqlite-object-cache-statistics.php

352 lines 8.6 KB

Raw Download Zip

1	<?php
2	/**
3	* Statistics class file.
4	*
5	* @package SQLite Object Cache
6	*/
7
8	if ( ! defined( 'ABSPATH' ) ) {
9	exit;
10	}
11
12	/**
13	* statistics class.
14	*/
15	class SQLite_Object_Cache_Statistics {
16
17	/**
18	* Associative array with selected cache items names most frequent first.
19	*
20	* @var array
21	*/
22	public $selected_names;
23
24	/**
25	* Associative array with descriptive statistics.
26	*
27	* @var array
28	*/
29	public $descriptions;
30	/**
31	* @var string
32	*/
33	private $start_time;
34	/**
35	* @var string
36	*/
37	private $end_time;
38
39	/**
40	* Initialize and load data.
41	*
42	* @return void
43	* @throws Exception Announce database failure.
44	*/
45	public function init() {
46	global $wp_object_cache;
47
48	$first = PHP_INT_MAX;
49	$last = PHP_INT_MIN;
50
51	$selected_names = [];
52	$opens = [];
53	$selects = [];
54	$inserts = [];
55	$deletes = [];
56	$RAMratios = [];
57	$RAMhits = 0;
58	$RAMmisses = 0;
59	$DISKratios = [];
60	$DISKhits = 0;
61	$DISKmisses = 0;
62
63	if ( ! method_exists( $wp_object_cache, 'sqlite_load_statistics' ) ) {
64	return;
65	}
66
67	foreach ( $wp_object_cache->sqlite_load_statistics() as $data ) {
68	$first = min( $data->time, $first );
69	$last = max( $data->time, $last );
70	$RAMhits += $data->RAMhits;
71	$RAMmisses += $data->RAMmisses;
72	$DISKhits += $data->RAMhits;
73	$DISKmisses += $data->RAMmisses;
74	$RAMratio = $data->RAMhits / ( $data->RAMhits + $data->RAMmisses );
75	$RAMratios[] = $RAMratio;
76	$DISKratio = $data->DISKhits / ( $data->DISKhits + $data->DISKmisses );
77	$DISKratios[] = $DISKratio;
78	$opens [] = $data->open;
79	$selects [] = $data->selects;
80	$inserts [] = $data->inserts;
81	$deletes[] = $data->deletes;
82
83	if ( is_array( $data->select_names ) ) {
84	foreach ( $data->select_names as $name ) {
85	if ( ! array_key_exists( $name, $selected_names ) ) {
86	$selected_names[ $name ] = 0;
87	}
88	$selected_names[ $name ] ++;
89	}
90	}
91	}
92	$duration = $last - $first;
93	if ( $duration > 0 ) {
94	arsort( $selected_names );
95	$descriptions = [
96	__( 'Start', 'sqlite-object-cache' ) => $this->descriptive_stats( $opens ),
97	__( 'RAM Hit Ratio', 'sqlite-object-cache' ) => $this->descriptive_stats( $RAMratios ),
98	__( 'Disk Hit Ratio', 'sqlite-object-cache' ) => $this->descriptive_stats( $DISKratios ),
99	__( 'Lookup', 'sqlite-object-cache' ) => $this->descriptive_stats( array_merge( ...$selects ) ),
100	__( 'Save', 'sqlite-object-cache' ) => $this->descriptive_stats( array_merge( ...$inserts ) ),
101	__( 'Delete', 'sqlite-object-cache' ) => $this->descriptive_stats( array_merge( ...$deletes ) ),
102	];
103
104	$this->descriptions = $descriptions;
105	$this->selected_names = $selected_names;
106	$date_format = get_option( 'date_format' ) . ' ' . get_option( 'time_format' );
107	$this->start_time = wp_date( $date_format, (int) $first );
108	$this->end_time = wp_date( $date_format, (int) $last );
109	}
110	}
111
112	/**
113	* Descriptive statistics for an array of numbers.
114	*
115	* @param array $a The array.
116	*
117	* @return array
118	*/
119	public function descriptive_stats( array $a ) {
120	$min = $this->minimum( $a );
121	$max = $this->maximum( $a );
122
123	return [
124	'n' => count( $a ),
125	'[min' => $min,
126	'median' => $this->percentile( $a, 0.5 ),
127	'mean' => $this->mean( $a ),
128	'p95' => $this->percentile( $a, 0.95 ),
129	'max]' => $max,
130	'range' => $max - $min,
131	'mad' => $this->mad( $a ),
132	'stdev' => $this->stdev( $a ),
133	];
134	}
135
136	/**
137	* The smallest value in an array.
138	*
139	* @param array $a The array.
140	*
141	* @return mixed\|null
142	*/
143	public function minimum( array $a ) {
144	sort( $a );
145
146	return count( $a ) > 0 ? $a[0] : null;
147	}
148
149	/**
150	* The largest value in an array.
151	*
152	* @param array $a The array.
153	*
154	* @return mixed\|null
155	*/
156	public function maximum( array $a ) {
157	sort( $a );
158
159	return count( $a ) > 0 ? $a[ count( $a ) - 1 ] : null;
160	}
161
162	/** Percentile.
163	*
164	* @param array $a dataset.
165	* @param number $p percentile as fraction 0-1.
166	*
167	* @return float
168	*/
169	public function percentile( array $a, $p ) {
170	$n = count( $a );
171	if ( ! $n ) {
172	return null;
173	}
174	sort( $a );
175	$i = (int) floor( $n * $p );
176	if ( $i >= $n ) {
177	$i = $n - 1;
178	}
179
180	return $a[ $i ];
181	}
182
183	/**
184	* Arithmetic mean.
185	*
186	* @param array $a dataset.
187	*
188	* @return number
189	*/
190	public function mean( array $a ) {
191	$n = count( $a );
192	if ( ! $n ) {
193	return null;
194	}
195	if ( 1 === $n ) {
196	return $a[0];
197	}
198	$acc = 0;
199	foreach ( $a as $v ) {
200	$acc += $v;
201	}
202
203	return $acc / $n;
204	}
205
206	/**
207	* Mean absolute deviation.
208	*
209	* @param array $a dataset.
210	*
211	* @return float\|int\|null
212	*/
213	public function mad( array $a ) {
214	$n = count( $a );
215	if ( ! $n ) {
216	return null;
217	}
218	if ( 1 === $n ) {
219	return 0.0;
220	}
221	$acc = 0;
222	foreach ( $a as $v ) {
223	$acc += $v;
224	}
225	$mean = $acc / $n;
226	$acc = 0;
227	foreach ( $a as $v ) {
228	$acc += abs( $v - $mean );
229	}
230
231	return $acc / $n;
232	}
233
234	/**
235	* Standard deviation.
236	*
237	* @param array $a dataset.
238	*
239	* @return float\|null
240	*/
241	public function stdev( $a ) {
242	$n = count( $a );
243	if ( ! $n ) {
244	return null;
245	}
246	if ( 1 === $n ) {
247	return 0.0;
248	}
249	$sum = 0.0;
250	$sumsq = 0.0;
251	foreach ( $a as $v ) {
252	$sum += $v;
253	$sumsq += ( $v * $v );
254	}
255	$mean = $sum / $n;
256
257	return sqrt( ( $sumsq / $n ) - ( $mean * $mean ) );
258	}
259
260	/**
261	* Render the statistics display.
262	*
263	* @return void
264	*/
265	public function render() {
266
267	echo '<h3>' . esc_html__( 'Cache performance statistics', 'sqlite-object-cache' ) . '</h3>';
268	if ( is_array( $this->descriptions ) ) {
269	echo '<p>' . esc_html( sprintf(
270	/* translators: 1 start time 2 end time both in localized format */
271	__( 'From %1$s to %2$s.', 'sqlite-object-cache' ),
272	$this->start_time, $this->end_time ) . ' ' . __( 'Times in microseconds.', 'sqlite-object-cache' ) ) . '</p>' . PHP_EOL;
273	echo '<table class="sql-object-cache-stats">' . PHP_EOL;
274	$first = true;
275	foreach ( $this->descriptions as $stat => $description ) {
276	if ( $first ) {
277	echo '<thead><tr>';
278	echo '<th scope="col">' . esc_html__( 'Item', 'sqlite-object-cache' ) . '</th>';
279	foreach ( $description as $item => $value ) {
280	echo '<th scope="col">' . esc_html( $item ) . '</th>' . PHP_EOL;
281	}
282	echo '</tr></thead><tbody>' . PHP_EOL;
283	$first = false;
284	}
285	echo '<tr>';
286	echo '<th scope="row">' . esc_html( $stat ) . '</th>';
287	foreach ( $description as $value ) {
288	echo '<td>' . esc_html( round( $value, 2 ) ) . '</td>';
289	}
290	echo '</tr>' . PHP_EOL;
291	}
292	echo '</tr></tbody></table>' . PHP_EOL;
293	} else {
294	echo '<p>' . esc_html__( 'No cache statistics recorded yet.', 'sqlite-object-cache' ) . '</p>';
295	}
296
297	if ( is_array( $this->selected_names ) && count( $this->selected_names ) > 0 ) {
298
299	$names = $this->selected_names;
300	uksort( $names, function ( $a, $b ) {
301	/* Descending order of frequency */
302	if ( $this->selected_names[ $a ] !== $this->selected_names[ $b ] ) {
303	return $this->selected_names[ $a ] > $this->selected_names[ $b ] ? - 1 : 1;
304	}
305	$as = explode( '\|', $a, 2 );
306	$bs = explode( '\|', $b, 2 );
307	/* Ascending order by group name */
308	if ( $as[0] !== $bs[0] ) {
309	return strnatcmp( $as[0], $bs[0] );
310	}
311	/* Ascending order by key name, handling numeric keys correctly. */
312	if ( is_numeric( $as[1] ) && is_numeric( $bs[1] ) ) {
313	if ( (float) $as[1] === (float) $bs[1] ) {
314	return 0;
315	}
316
317	return ( (float) $as[1] ) < ( (float) $bs[1] ) ? - 1 : 1;
318	}
319
320	return strnatcmp( $as[1], $bs[1] );
321	} );
322
323	echo '<h3>' . esc_html__( 'Most frequently looked up cache items', 'sqlite-object-cache' ) . '</h3>' . PHP_EOL;
324
325	echo '<table class="sql-object-cache-items">' . PHP_EOL;
326	$count_threshold = - 1;
327	$first = true;
328	foreach ( $names as $name => $count ) {
329	if ( $first ) {
330	echo '<thead><tr>';
331	echo '<th scope="col">' . esc_html__( "Cache Group", 'sqlite-object-cache' ) . '</th>';
332	echo '<th scope="col">' . esc_html__( "Cache Key", 'sqlite-object-cache' ) . '</th>';
333	echo '<th scope="col">' . esc_html__( "Count", 'sqlite-object-cache' ) . '</th>';
334	echo '</tr></thead><tbody>' . PHP_EOL;
335	$count_threshold = (int) ( $count * 0.7 );
336	$first = false;
337	}
338	if ( $count < $count_threshold ) {
339	break;
340	}
341	$splits = explode( '\|', $name, 2 );
342	echo '<tr>';
343	echo '<td>' . esc_html( $splits[0] ) . '</td>';
344	echo '<td>' . esc_html( $splits[1] ) . '</td>';
345	echo '<td>' . esc_html( $count ) . '</td>';
346	echo '</tr>' . PHP_EOL;
347	}
348	}
349	echo '</tbody></table>';
350	}
351	}
352