Using Eclipse's PHP Profiler, I have discovered a bottleneck in my code on a method that is called many times. The problem is that I cannot tell what parameters were passed in to the method to determine how to reproduce the symptom.
I have tried surrounding the code that the profiler is reporting as taking a full second to complete with the following:
$startTime = microtime(true);
$safe_text = wp_check_invalid_utf8( $text );
$endTime = microtime(true);
$time = $endTime - $startTime;
if ($time > .05) {
error_log('Time: ' . $time . ' text [' . $text . ']');
}
I never have a single hit in the error log for this, yet the profiler will continue to report one as taking a full second to complete. Refreshing the page in the browser does indicate that there is significant slowness.
I have this same problem in 3 different areas of my code and knowing what was being passed in to the methods at the time they run slowly may be of assistance in fixing the problem. Is there any way to determine what is being passed in to the intermittently slow method when it is running slowly?
It is possible to set this up using xdebug which is what Eclipse uses for profiling, however it's disabled by default because recording this data in a project that makes a lot of calls or passes large data structures would quickly overwhelm your available memory.
I recommend you do manual logging as you are currently doing although I'd start by measuring the total time of all calls to wp_check_invalid_utf8 to make sure you do infact have a problem in just that part and that is isn't just a problem caused by the Eclipse profiler itself. Once you've established the total time is more than you would like, then start logging individual calls and their parameters.
Related
I have some concerns about my PHP file, which is processing too long.
I'm using XAMPP.
The problem is, that when i use too many methods of my classes, the PHP file loads too slow or it executes too slow.
Here's my example code:
class Sample {
public function show() {
echo 'test';
}
}
$classObject = new Sample();
$classObject->show();
When i run the PHP code above, it takes only i think 1.5s, but if i add more method calls like this:
$classObject = new Sample();
$classObject->show();
$classObject->show();
the PHP code takes almost 3s while executing.
Is there a way to solve this problem?
I already found out what is the problem is when i used oop style php while fetching data from my database it takes long secs before it gonna execute but when I used procedural php style it executes faster.
Firstly, you should take a look at some PHP debugging techniques, because i dont see any attempt of debugging in your code sample.
To your problem:
What you've described is an issue, that can be but must not be a fault of PHP. The thing is, you have to understand how request processing works ... in your case (XAMPP + PHP) it goes like this:
WebServer start:
XAMPP starts Apache (or Tomcat/or whatever WebServer you're using)
Apache starts PHP binary
PHP loads the configuration (php.ini)
The request:
You'll start a web browser (doesn't matter which one)
You'll enter a web address (with or without a specific path - URI)
Then happens some DNS things - that's NOT important for you now
The browser sends a plain-text document on the server via the HTTP protocol, which communicates over TCP - also not so important for you at this time
The WebServer receives a HTTP request and begins the processing
The WebServer runs your PHP script in the already running PHP binary and awaits the ouput
The response
Then the WebServer takes the output of your script and sends it back to the browser
The browser decides (by the headers) how (and if) the content will be displayed to you
Then the browser begins displaying the response content - in your case a HTML or a plain-text document
While drawing the document, the browser begins processing all JavaScript and CSS on the way (up to down)
With this knowledge you need to find out WHERE on the way is the delay taking up time.
The first thing you should do, is to take a look on how long your script is being processed, so:
<?php
$start_time = microtime(true);
$classObject = Sample();
$classObject->show();
$classObject->show();
echo 'Processing took: ' . number_format(microtime(true) - $start_time, 6, '.', '') . ' seconds';
Then, you should look into some Developer Tool your browser provides, for example DevTools in Google Chrome (very good for debugging, though not the best) - hit F12 to open it.
You'll see something like this:
Time is the duration between the time, the request was fully sent and the time, the response was fully received
Load is the sum of durations of all the requests that were done at that moment
Finish is the duration between the time the first request was fully sent and the time the last response was fully received
DOMContentLoaded is the duration of rendering the entire document (browser/client side)
When you have all of this specific duartions, you can decide, where probably will be the problem :)
I had a site working nicely in PHP. Then an acquaintance who works at Google got in my ear about how AJAX is the thing. So now I've rejigged the site to be in just HTML & javascript on the client-side making AJAX JSON calls to PHP scripts calling MySQL on the server side. Good caching, no page reloads. It was a good idea.
My question now, however, is this: How much faster might the site run if the server side was in a compiled language (say, C or C++) rather than PHP? (My original prototype was in C - in the terminal!) The PHP scripts are all basic security processing and then database calls to return JSON. How can you benchmark relative speeds? Just using firebug POST data in the console? Or is there a better way?
Thanks :)
if it is that simple, php interpretation will be a tiny fraction of the execution time, most of which will be taken by the connection to the db server. You can always look at Facebook's HipHop - http://developers.facebook.com/blog/post/358/ though
For benchmarking, something like
// first line of your code
$start_time = microtime( $get_as_float = TRUE );
// last line of your code
$time_end = microtime( $get_as_float = TRUE );
$execution_time = $time_end - $start_time;
echo '<!-- executed in: ', $execution_time , ' seconds -->';
will go a long way
I wouldn't use the times in Firebug as those depend on your connection speed/quality etc
I know people complain usually about scripts not working, but here is a case where it keeps working even if I want it to stop.
I have a CSV parser that analyzes lines and inserts entries in a DB table. I am using PDO and Zend Framwork for the project. The code works fine.. too fine in fact.
public function save()
{
$memory_limit = ini_get('memory_limit');
ini_set('memory_limit', '512M');
$sql = "
INSERT INTO my_table (
date_start,
timeframe,
type,
country_to,
country_from,
code,
weight,
value
) VALUES (?,?,?,?,?,?,?,?)
ON DUPLICATE KEY UPDATE
weight = VALUES(weight),
value = VALUES(value)
";
if ($this->test_mode) {
echo $sql;
return;
}
$stmt = new Zend_Db_Statement_Pdo($this->_db, $sql);
foreach($this->parsed_data as $entry){
$stmt->execute(array_values($entry));
$affected_rows = $stmt->rowCount();
if ($affected_rows){
$this->_success = true;
}
}
unset($this->parsed_data, $stmt, $sql);
ini_set('memory_limit', $memory_limit);
}
The script takes various seconds to complete as I am parsing a big file. The problem appears when I am trying to stop the script, with ESC or even by closing the page. The script does not stop until it finishes to insert all entries. Not even an Apache reload is not fixing this, probably a restart will do it.
I am thinking that this is not normal behaviour and maybe I am doing something wrong so I am asking for suggestions.
Thanks.
UPDATE
ignore_user_abort is off (default behaviour) so user abort should be considered..
I'm pretty sure that's standard PHP behaviour - just because the browser goes away doesn't mean it won't stop processing the script. (Although restarting Apache, etc. will achieve this goal.)
To change this behaviour, you can use ignore_user_abort.
That said, "PHP will not detect that the user has aborted the connection until an attempt is made to send information to the client", which I suspect may be the issue you're experiencing.
See the above link and the PHP runtime configuration information for more info.
It is not wrong. Your tries won't work because:
ESCape - because it is totally unrelated to the working of a page - most browsers don't actually react to it
closing (or refreshing) the page - again, not related - the SERVER is doing something, and PHP will NOT stop when the client-side stops - server can't actually know if the client closed or refreshed a page
Apache reload - won't kill the PHP forked process
Restart WOULD do it - this will kill PHP processes and stuff. Although it is kinda troublesome.
Way to do this (if the long execution is undesirable), is to actually set an execution time limit, using PHP function set_time_limit(), or to make the parsing more optimal (if it is not).
I have php scripts that call perl scripts to do various things and sometimes I get it where it just goes on and on without getting a response back, this is based on the variable that is being passed to the perl script and I am doing a lot of different ones in succession so I can't get really debug it directly since I don't have a response from perl...
I would really like to just be able to set a php function or block of code to timeout after a certain number of seconds.. I have been searching on this but haven't found anything yet on how to do this,
I was thinking something like this could work but I don't think it would dynamically update the $time variable, but maybe there is a way to get this to work? Any advice is appreciated
$time = time();
$timeout = $time + 5; //just as an example
do {
// do stuff
} while ($time < $timeout)
Your best bet would be to use proc_open, sleep for your timeout amount and then call proc_terminate if the process still hasn't completed.
See http://us3.php.net/manual/en/book.exec.php for details on the proc_* family.
Well, I'm not so sure this question would have an answer based on how I asked it, so what I am going to do is do the perl call where php doesn't wait for a response and have perl write the output to a text file, then have php read this after specified number of seconds, I think this is the simplest way to do this, its just for a small app i am running on a local server
A site I am working with is starting to get a little sluggish, and I would like to refine it. I think the problem is with the PHP, but I can't be sure. How can I see how long functions are taking to perform?
If you want to test the execution time :
<?php
$startTime = microtime(true);
// Your content to test
$endTime = microtime(true);
$elapsed = $endTime - $startTime;
echo "Execution time : $elapsed seconds";
?>
Try the profiler feature in XDebug or Zend Debugger?
Two things you can do.
place Microtime calls everywhere although its not convenient if you want to test more than one function. So there is a simpler way to do it a better solution if you want to test many functions which i assume you would like to do.
just have a class (click on link to follow tutorial) where you can test how long all your functions take. Rather than place microtime everywhere. you just use this class. which is very convenient
http://codeaid.net/php/calculate-script-execution-time-%28php-class%29
the second thing you can do is to optimize your script is by taking a look at the memory usage.
By observing the memory usage of your scripts, you may be able optimize your code better.
PHP has a garbage collector and a pretty complex memory manager. The amount of memory being used by your script. can go up and down during the execution of a script. To get the current memory usage, we can use the memory_get_usage() function, and to get the highest amount of memory used at any point, we can use the memory_get_peak_usage() function.
view plaincopy to clipboardprint?
echo "Initial: ".memory_get_usage()." bytes \n";
/* prints
Initial: 361400 bytes
*/
// let's use up some memory
for ($i = 0; $i < 100000; $i++) {
$array []= md5($i);
}
// let's remove half of the array
for ($i = 0; $i < 100000; $i++) {
unset($array[$i]);
}
echo "Final: ".memory_get_usage()." bytes \n";
/* prints
Final: 885912 bytes
*/
echo "Peak: ".memory_get_peak_usage()." bytes \n";
/* prints
Peak: 13687072 bytes
*/
http://net.tutsplus.com/tutorials/php/9-useful-php-functions-and-features-you-need-to-know/
PK
You can also make it manually, by recording microtime() value in various places, like this:
<?
$TIMER['start']=microtime(TRUE);
// some code
$query="SELECT ...";
$TIMER['before q']=microtime(TRUE);
$res=mysql_query($query);
$TIMER['after q']=microtime(TRUE);
while ($row = mysql_fetch_array($res)) {
// some code
}
$TIMER['array filled']=microtime(TRUE);
// some code
$TIMER['pagination']=microtime(TRUE);
/and so on
?>
and then visualize it
<?
if ('127.0.0.1' === $_SERVER['REMOTE_ADDR']) {
echo "<table border=1><tr><td>name</td><td>so far</td><td>delta</td><td>per cent</td></tr>";
reset($TIMER);
$start=$prev=current($TIMER);
$total=end($TIMER)-$start;
foreach($TIMER as $name => $value) {
$sofar=round($value-$start,3);
$delta=round($value-$prev,3);
$percent=round($delta/$total*100);
echo "<tr><td>$name</td><td>$sofar</td><td>$delta</td><td>$percent</td></tr>";
$prev=$value;
}
echo "</table>";
}
?>
an IP address check implies that we are doing this profiling on the working site
Though I doubt it's PHP itself. Most likely it's database. So, pay most attention to query execution timing.
however, a "site" term is very broad. It includes also JS, CSS, images and stuff. So, I'd suggest to start form FirebFug's Net page to see what part of whole page takes more time.
Of course, refining can be done only after analysis of profiling results, and cannot be advised here without it.
Your best bet is Xdebug. Im happy as it comes bundled in my PHPed IDE. I can get profiler data at the click of a button.
So maybe you could consider that.
I had similar issues and so I created 2 new tables on the database and two new functions. One was audit_sql and the other was audit_code. Because I used an SQL abstraction class it was easy to time every single SQL call (I used php microtime as some others have suggested). So, I called microtime before and after the SQL call and stored the results on the database.
Similarly with pages. I called microtime at the start and end of each page and if necessary at the start and end of functons, divs - whatever I thought might be a culprit.
The general results were:
SQL calls to MySQL were almost instantaneous and were nto a problem at all. The only thing I would say is that even I was surprised at the number being executed! The site is generated from the database - even the menus, permissions etc. To produce the home page the SQL calls were measured in the 100s.
PHP was not the culprit. This was even more instantaneous that MySQL.
The culprit was.... (big build up!) calls to You Tube and Picassa and other sites like that. I host videos and photo albums on the site (well, I don't actually store them - they are stored on YT etc.) and on the home page are thumbnails that are extracted from You Tube and the like via the You Tube PHP API/Zend Framework. Because this is all http based to the other sites, each one was taking 1, 2 or 3 seconds. This was causing those divs containing these to take between 6 and 12 seconds and the home page up to 17 seconds.
The solution - store all thumbnails on my server. The first time one has to be served from the remote site (YT, Picassa etc.) so do that and then store it on your own site. Future times, you check if you have it and if so serve it always from your server. Cuts the page load time down to 2-3 seconds tops. Granted the first person to view the first home page load after someone has loaded more videos/images will take some time, but not thereafter. People will put a long one-off page load time down to their connection/the internet in general. Too many slow loads of your site and they will stop visiting!
I hope that helps somewhat.