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I've an already developed and running social website like 'Facebook'.
This website has been developed using PHPFox v3.0.7(which is a social networking platform created in php).
The website functions are working well, no issues with them.
The main, major and serious issue I'm facing with the website is the slow execution speed. For any kind of operation it takes too much time and user has to wait for that much time. This really irritates the user and is affecting the performance of a website.
So, I did research on 'Facebook'- The World's Largest Social Networking Website developed in PHP. If 'Facebook' can execute at rapid speed in spite of heavy user load and continuous operations why can't my site?
First thing is the site is developed using a framework called 'PHPFox' so the entire Database design, caching and all other things have been managed by the framework itself, I can't change the framework's settings but ultimately I want to increase the execution speed of my website.
So how should I achieve it? If you have any best in class solution please provide me the guidance for it.
Any kind of help would be highly appreciated.
Please feel free to ask me any of the queries you have regarding the issue I'm facing.
Thanks.
There are several ways you can increase the speed.
Using CDN,
Enable caching,
Using load balancing server,
Enable compression,
Enabling bootstrap,
Optimize database and db driver
You can use the following server speedup method
Enabling mod_deflacte
Enabling memchached
I have faced the same problem earlier when working on PHPFox and most of the things can be handled from the admin control panel.
By using memcached, i have resolved the speed issue. You can follow the simple steps which are mentioned in the knowledge base of PHPFox and i hope you will find some solution. how-to-enable-memcached
First of all facebook uses HHMV(HipHop Virtual Machine) which is an execution engine for PHP, ie their PHP code is first transformed into intermediate HipHop bytecode (HHBC), which is then dynamically translated into the x86-64 machine code, optimized and natively executed.
Thus everytime you login to facebook ,you just run the highly
efficient machine code.
I assume your site do not have HHMV , so here are some few tools & tips to boost PHP running websites,
memcached
cassandra
Optimizing db driver
Using msqli instead of mysql
Using a server with better configuration.
Using minified versions of jquery & bootstrap (ie bootstrap.min.js & jquery.min.js).
Hi In your main question, what you are asking is for the advice to increase the performance of your PHPFox application. Whereas, in the different note section, you are looking for the solution to send the Push-Notifications.
I will be answering you regarding the 'Increasing the performance of your website'.
As you must be aware, performance tuning/optimization is the bigger task. It has various stages as listed by '#Myself Malay'. Some of them can be done quick and others will take time. So you need to know them, prioritize them. For ex: Reducing the requests of JS and CSS files, by making them load using the CDN, can be accomplished quickly. Serving your resources (HTML, CSS, JS) in compressed form (gzip) also can be done quickly.
Optimizing your queries will be time consuming. Enabling Cache should be quick. If you want to establish the load balancers then it will take some time.
Here, I am adding some reference links regarding the PHPFox, which will help you.
http://www.ipragmatech.com/phpfox3-performance-xcache-apc-memcached.html#.VXkzXt93M_M
How to optimize your database tables in PHPFox
Speedup PHPFox V3
PHPFox - Optimization Settings
Note: Some of the tweaks may require the modification of the core files. Be careful, while doing so as they will make auto-update very difficult. Always take your code and DB backup during modification to your core files. Make a document about the changes you have done as which files, where why etc, which will help you to re-apply all those changes again, in case of updating your code to new version.
Below, I am adding some of the links, which will help you in understanding the Performance Optimization to the next level
Books for Building Scalable Web Applications? (DB Performance/Tuning, Networking, General Performance, etc.)
Scalability and Performance of Web Applications, Approaches?
My personal favorite book is: Scaling PHP Applications by Steve Corona. This book is the best reference ever available for the PHP Developers.
Eventhough I am not able to give any direct solution to your problem, hope this helps upto certain extent. All the best :-)
First of all, stop comparing your Phpfox site with Facebook. Facebook has hundreds of thousands of programmers working day and night to keep the performance up. It is a horrable truth that PHP is a slow server side scripting language. If your site improves, it's performance goes down. Fortunately, there are some tools available that can be used for increasing the overall performance of your website. Some of them are Memcached, Cassendra, Varnix etc. You can use CD networks to serve data faster. Choosing a good hosting server also helps to make your site ready for heavy traffic.
Facebook uses over 100 unique technologies to keep the site going with a respectable speed. Hiphop PHP is a technology that was developed by the company itself and is used to compile PHP scripts faster than any native C++ compiler. Hiphop makes PHP Codes to execute 30-50% faster. Well, HHVM is an alternative to Hiphop PHP and is available for free but requires nginx. Think again, moving from Apache to nginx is not a good decision if you are just a beginner.
this is my first question here, which is regarding a specific website optimization.
A few moths ago, we launched [site] for one of our clients which is some kind of community website.
Everything works great, but now this website is getting bigger and it shows some slowness when the pages are loading.
The server specs:
PHP 5.2.1 (i think we need to upgrade on 5.3 to make use of the new garbage collector)
Apache 2.2
Quad Core Xeon Processor # 2,8 Ghz and 4 GB DDR 3 RAM.
XCACHE 1.3 (we added this a few months ago)
Mysql 5.1 (we are using innodb as engine)
Codeigniter framework
Here is what we did so far and what we intend to do further :
Beside xcache, we don't really use a caching mechanism because most of the content comes live and beside this, we didn't wanted to optimize prematurely because we didn't know what to expect as far as the traffic flow.
On the other hand, we have installed memcached and we want to implement a cache system based on memcached.
Regarding the database structure, we have reached 3NF with most of our tables, and yes we have some slow queries(which we plan to optimize) but i think because the tables that produce slow queries are the one for blog comments(~44,408 rows) / user logs tracking (~725,837 rows) / user comments (~698,964 rows) etc which are quite big tables. The entire database is 697.4 MB in size for now.
Also, here are some stats for January 2011:
Monthly unique visitors: - 127.124
Monthly unique views: 4.829.252
Monthly unique visits: 242.708
Daily average:
Unique new visitors: 7.533
Unique new views : 179.680
Just let me know if you need more details.
Any advice is highly appreciated.
Thank you.
When it come to performance issue, there is no golden rule or labelled sticky note that first tell that is related to database. Maybe what i could suggest is to do performance profiling and there are many free and paid tools over the Internet that allows you to do so.
First start of with web server layer, make sure everything is done correctly and optimized as what is be possible.
Then move on to next layer (which i assume is your database). Normally from layman perspective whenever someone mentioned InnoDB MySQL, we assume there are indexes being created to optimize and search operations. The usage of indexes also quite important because you don't want to indexing something wrong and make things worse. My advise to this is to get a DBA equivalent personnel to troubleshoot using a staging environment.
Another tricks you could possibility look at is the contents, from web page contents to database data, make sure you show/keep data where is needed only, do no store unnecessary information into database and using smart layout on the webpage. A cut down of a seconds or two might do a big difference in terms of usability and response time.
It is very hard to explain the detail here unless we have in-depth information about your application, its architecture and your environment, but above are some commonly used direction people use to troubleshoot such incident.
Good luck!
This site has excellent resources http://www.websiteoptimization.com/
The books that are mentioned are excellent. There are just too many techniques to list here and we do not know what you have tried so far.
Sorry for the delay guys, i have been very busy to find the issue and i did it.
Well, the problem was because of apache mostly, i had an access log of almost 300 GB which at midnight was parsed to generate webalizer stats. Mostly when this was happening the website was very very slow. I disabled webalizer for the domain, cleared the logs, and what to see, it is very fast again, doesn't matter the hour you access it.
I now only have just a few slow queries that i tend to fix today.
I also updated to CI 2.0 Reactor as suggested and started to use the memcached driver.
Who would knew that apache logs can be so problematic...
Based on the stats, I don't think you are hitting load problems... on a hunch, I would look to the database first. Database partitioning might be a good place to start.
But you should really do some profiling of your application first. How much time is spent in the application versus database. Are there application methods that are using lots of time and just need some tweaking? Are database queries not written efficiently? Do you need more or better database indices?
Everything looks pretty good-- if upgrading codeigniter is an option, the new codeigniter 2.0 (reactor) adds support for memcache (New Cache driver with file system, APC and memcache support). Granted you're already using xcache, these new additions may be worth looking at.
When cache objects weren't enough for our multi-domain platform that saw huge traffic, we went the route of throwing more hardware at it-- ram, servers/database. Then we moved to database clustering to handle single account forecasted heavy load. And now switching from apache to nginx... It's a never ending battle, but what worked for us was being smart about what we cached and increasing server memory then distributing this load across servers...
Cache as many database calls as you can. In my CI application I have a settings table that rarely changes, so I cache all calls made to it as I am constantly querying the settings table.
Cache your views and even your controllers as well. I tend to cache basically as much as I can in my CI applications and then refresh the cache when a file changes.
Only autoload important libraries, models and helpers. I've seen people autoload up to 10 libraries and on-top of that a few helpers and then a model. You only really need to autoload the database and session libraries if you are using them.
Regarding point number 3, are you autoloading many things in your config/autoload.php file by any chance? It might help speed things up only loading things you need in your controllers as you need them with exception of course the session and database libraries.
I installed Drupal common from acquia and using it for my college Intranet Website. I configured it on Ubuntu lucid lynx Desktop edition running latest XAMPP. I want to increase the performance of the website. My databse server and webserver is on same machine.
Can any one suggest methos to increase the performance on following point
What should be the ideal hardware configuration
What parameters should i change in PHP to run it for best performance?
How can I optimize apache and My SQL to get best performance out of both??
are there tweaks in drupal which can make it more faster?
Are there any additional packages for caching etc which can improve the speed??
Also, try Varnish if you're using PressFlow, as suggested by berkes. It helps a lot if you have to serve content for anonymous users.
Varnish can cache in memory all the content that Drupal produces, reducing hits to your web server and database.
Here a good start point for configuring Varnish with Pressflow:
https://wiki.fourkitchens.com/display/PF/Configure+Varnish+for+Pressflow
Google some for more details.
And don't forget about non Drupal related optimization, like reducing the number of http requests, serving web page elements from different domains to reduce browser pipelining, etc. Use YSlow and follow Yahoo's excellent rules. Google for "yahoo Best Practices for Speeding Up Your Web Site" (can't include link due to SO limitation for new users).
Is not specific for Drupal, but for every PHP setup. More general: for each web-app. I advise you to start with O'Reilly's Building Scalable Websites.
See above. For Drupal, note the memory limit; many people just crank it up to rediculous values; after logic: Drupal needs more then 38MB, I'll just give it 250MB, to be safe.
Again, see above. For Drupal, pay extra attention to the amount of queries. If you focus on Slow Queries only, you may miss that single tiny query hammering your DB 100+ times per request.
Lots. My advice is to start looking at pressflow, an optimised Drupal. It has all the tweaks you are looking for built in. And more.
Yes. Many-, but start with memcached. And if you rely on search a lot, consider moving search to SOLR search.
Many more tips for starters can be found at Drupal performance Blog
The question you ask is very broad, so it is hard to give any specifics in answers. A good place to start is drupal's own handbook on performance tuning.
I would also highly recommend the boost module if your site serves largely anonymous users, as this allows requests to not even go to drupal and be served entirely from a static cache.
Drupal's Devel module has a Performance module that will log memory usage and access times to the Reports section of your site.
Use this to determine which pages on your site are slow.
Load xdebug (a PHP extension) and turn on the profiling feature. Make requests to your performance-intensive pages and it will create (very large) dumps of the entire request. Open up the cache file in a program like KCacheGrind or WinCacheGrind and you will be able to see every function call that Drupal made when building the page. From here you can see which parts are slowest and optimize them.
This should get you a good 30-80% improvement in performance if you have a slow site. In my experience, there's usually a few blocks or views that account for a huge part of any performance issues.
Pro Drupal 7 Development has a whole section regarding fine-tuning called "optimizing drupal".
I think you will find it quite interesting. It also discusses hardware architectures which is of your interest.
Regarding the 4th question, you can for a start checkout the boost module and disable modules you are not using.
Additionally, for improving page-performance you can enable page caching from Configuration -> Performance. In the same page you can use the aggregate and compress CSS(JS) files into one", in this way you reduce the number of HTTP requests per page and the overall size of the downloaded page.
You should also consider if CRON is setup. Not running cron can fill up the db with log , stale cache and other "garbage".
A last suggestion is to convert your db from MyIsam to InnoDB, but I think this requires some investigation because it not always the case that InnoDB is faster. With InnoDb there is less time lost from table locking while MyISAM is faster in table readings.
I've written a site CMS from scratch, and now that the site is slowly starting to get traffic (30-40k/day) Im seeing the server load a lot higher than it should be. It hovers around 6-9 all the time, on a quad core machine with 8gb of ram. I've written scripts that performed beautifully on 400-500k/day sites, so I'd like to think Im not totally incompetent.
I've reduce numbers of queries that are done on every page by nearly 60% by combining queries, eliminating some mysql calls completely, and replacing some sections of the site with static TXT files that are updated with php when necessary. All these changes affected the page execution time (index loads in 0.3s, instead of 1.7 as before).
There is virtually no IOwait, and the mysql DB is just 30mb. The site runs lighttpd, php 5.2.9, mysql 5.0.77
What can I do to get to the bottom of what exactly is causing the high load? I really wanna localize the problem, since "top" just tells me its mysql, which hovers between 50-95% CPU usage at all times.
Use EXPLAIN to help you optimize/troubleshoot your queries. It will show you how tables are referenced and how many rows are being read. It's very useful.
Also if you've made any modifications to your MySQL configuration, you may want to revisit that.
The best thing you can do is to profile your application code. Find out which calls are consuming so much of your resources. Here are some options (the first three Google hits for "php profiler"):
Xdebug
NuSphere PhpED
DBG
You might have some SQL queries that are very slow, but if they are run infrequently, they probably aren't a major cause of your performance problems. It may be that you have SQL queries that are more speedy, but they are run so often that their net impact to performance is greater. Profiling the application will help identify these.
The most general-purpose advice for improving application performance with respect to database usage is to identify data that changes infrequently, and put that data in a cache for speedier retrieval. It's up to you to identify what data would benefit from this the most, since it's very dependent on your application usage patterns.
As far as technology for caching, APC and memcached are options with good support in PHP.
You can also read through the MySQL optimization chapter carefully to identify any improvements that are relevant to your application.
Other good resources are MySQL Performance Blog, and the book "High Performance MySQL." If you're serious about running a MySQL-based website, you should be consulting these resources frequently.
mytop is a good place to start. It's basically top for MySQL, and will give you a window into what exactly your DB is doing:
http://jeremy.zawodny.com/mysql/mytop/
Noah
It could be any number of reasons, so it could take a lot of proding. A good first step would be to turn on the slow query log, and go over it by hand or with a parser. You can pick specific heavily used, slow queries to optimize (perhaps ones that hit something unindexed)
A site I built with Kohana was slammed with an enormous amount of traffic yesterday, causing me to take a step back and evaluate some of the design. I'm curious what are some standard techniques for optimizing Kohana-based applications?
I'm interested in benchmarking as well. Do I need to setup Benchmark::start() and Benchmark::stop() for each controller-method in order to see execution times for all pages, or am I able to apply benchmarking globally and quickly?
I will be using the Cache-library more in time to come, but I am open to more suggestions as I'm sure there's a lot I can do that I'm simply not aware of at the moment.
What I will say in this answer is not specific to Kohana, and can probably apply to lots of PHP projects.
Here are some points that come to my mind when talking about performance, scalability, PHP, ...
I've used many of those ideas while working on several projects -- and they helped; so they could probably help here too.
First of all, when it comes to performances, there are many aspects/questions that are to consider:
configuration of the server (both Apache, PHP, MySQL, other possible daemons, and system); you might get more help about that on ServerFault, I suppose,
PHP code,
Database queries,
Using or not your webserver?
Can you use any kind of caching mechanism? Or do you need always more that up to date data on the website?
Using a reverse proxy
The first thing that could be really useful is using a reverse proxy, like varnish, in front of your webserver: let it cache as many things as possible, so only requests that really need PHP/MySQL calculations (and, of course, some other requests, when they are not in the cache of the proxy) make it to Apache/PHP/MySQL.
First of all, your CSS/Javascript/Images -- well, everything that is static -- probably don't need to be always served by Apache
So, you can have the reverse proxy cache all those.
Serving those static files is no big deal for Apache, but the less it has to work for those, the more it will be able to do with PHP.
Remember: Apache can only server a finite, limited, number of requests at a time.
Then, have the reverse proxy serve as many PHP-pages as possible from cache: there are probably some pages that don't change that often, and could be served from cache. Instead of using some PHP-based cache, why not let another, lighter, server serve those (and fetch them from the PHP server from time to time, so they are always almost up to date)?
For instance, if you have some RSS feeds (We generally tend to forget those, when trying to optimize for performances) that are requested very often, having them in cache for a couple of minutes could save hundreds/thousands of request to Apache+PHP+MySQL!
Same for the most visited pages of your site, if they don't change for at least a couple of minutes (example: homepage?), then, no need to waste CPU re-generating them each time a user requests them.
Maybe there is a difference between pages served for anonymous users (the same page for all anonymous users) and pages served for identified users ("Hello Mr X, you have new messages", for instance)?
If so, you can probably configure the reverse proxy to cache the page that is served for anonymous users (based on a cookie, like the session cookie, typically)
It'll mean that Apache+PHP has less to deal with: only identified users -- which might be only a small part of your users.
About using a reverse-proxy as cache, for a PHP application, you can, for instance, take a look at Benchmark Results Show 400%-700% Increase In Server Capabilities with APC and Squid Cache.
(Yep, they are using Squid, and I was talking about varnish -- that's just another possibility ^^ Varnish being more recent, but more dedicated to caching)
If you do that well enough, and manage to stop re-generating too many pages again and again, maybe you won't even have to optimize any of your code ;-)
At least, maybe not in any kind of rush... And it's always better to perform optimizations when you are not under too much presure...
As a sidenote: you are saying in the OP:
A site I built with Kohana was slammed with
an enormous amount of traffic yesterday,
This is the kind of sudden situation where a reverse-proxy can literally save the day, if your website can deal with not being up to date by the second:
install it, configure it, let it always -- every normal day -- run:
Configure it to not keep PHP pages in cache; or only for a short duration; this way, you always have up to date data displayed
And, the day you take a slashdot or digg effect:
Configure the reverse proxy to keep PHP pages in cache; or for a longer period of time; maybe your pages will not be up to date by the second, but it will allow your website to survive the digg-effect!
About that, How can I detect and survive being “Slashdotted”? might be an interesting read.
On the PHP side of things:
First of all: are you using a recent version of PHP? There are regularly improvements in speed, with new versions ;-)
For instance, take a look at Benchmark of PHP Branches 3.0 through 5.3-CVS.
Note that performances is quite a good reason to use PHP 5.3 (I've made some benchmarks (in French), and results are great)...
Another pretty good reason being, of course, that PHP 5.2 has reached its end of life, and is not maintained anymore!
Are you using any opcode cache?
I'm thinking about APC - Alternative PHP Cache, for instance (pecl, manual), which is the solution I've seen used the most -- and that is used on all servers on which I've worked.
See also: Slides APC Facebook,
Or Benchmark Results Show 400%-700% Increase In Server Capabilities with APC and Squid Cache.
It can really lower the CPU-load of a server a lot, in some cases (I've seen CPU-load on some servers go from 80% to 40%, just by installing APC and activating it's opcode-cache functionality!)
Basically, execution of a PHP script goes in two steps:
Compilation of the PHP source-code to opcodes (kind of an equivalent of JAVA's bytecode)
Execution of those opcodes
APC keeps those in memory, so there is less work to be done each time a PHP script/file is executed: only fetch the opcodes from RAM, and execute them.
You might need to take a look at APC's configuration options, by the way
there are quite a few of those, and some can have a great impact on both speed / CPU-load / ease of use for you
For instance, disabling [apc.stat](https://php.net/manual/en/apc.configuration.php#ini.apc.stat) can be good for system-load; but it means modifications made to PHP files won't be take into account unless you flush the whole opcode-cache; about that, for more details, see for instance To stat() Or Not To stat()?
Using cache for data
As much as possible, it is better to avoid doing the same thing over and over again.
The main thing I'm thinking about is, of course, SQL Queries: many of your pages probably do the same queries, and the results of some of those is probably almost always the same... Which means lots of "useless" queries made to the database, which has to spend time serving the same data over and over again.
Of course, this is true for other stuff, like Web Services calls, fetching information from other websites, heavy calculations, ...
It might be very interesting for you to identify:
Which queries are run lots of times, always returning the same data
Which other (heavy) calculations are done lots of time, always returning the same result
And store these data/results in some kind of cache, so they are easier to get -- faster -- and you don't have to go to your SQL server for "nothing".
Great caching mechanisms are, for instance:
APC: in addition to the opcode-cache I talked about earlier, it allows you to store data in memory,
And/or memcached (see also), which is very useful if you literally have lots of data and/or are using multiple servers, as it is distributed.
of course, you can think about files; and probably many other ideas.
I'm pretty sure your framework comes with some cache-related stuff; you probably already know that, as you said "I will be using the Cache-library more in time to come" in the OP ;-)
Profiling
Now, a nice thing to do would be to use the Xdebug extension to profile your application: it often allows to find a couple of weak-spots quite easily -- at least, if there is any function that takes lots of time.
Configured properly, it will generate profiling files that can be analysed with some graphic tools, such as:
KCachegrind: my favorite, but works only on Linux/KDE
Wincachegrind for windows; it does a bit less stuff than KCacheGrind, unfortunately -- it doesn't display callgraphs, typically.
Webgrind which runs on a PHP webserver, so works anywhere -- but probably has less features.
For instance, here are a couple screenshots of KCacheGrind:
(source: pascal-martin.fr)
(source: pascal-martin.fr)
(BTW, the callgraph presented on the second screenshot is typically something neither WinCacheGrind nor Webgrind can do, if I remember correctly ^^ )
(Thanks #Mikushi for the comment) Another possibility that I haven't used much is the the xhprof extension : it also helps with profiling, can generate callgraphs -- but is lighter than Xdebug, which mean you should be able to install it on a production server.
You should be able to use it alonside XHGui, which will help for the visualisation of data.
On the SQL side of things:
Now that we've spoken a bit about PHP, note that it is more than possible that your bottleneck isn't the PHP-side of things, but the database one...
At least two or three things, here:
You should determine:
What are the most frequent queries your application is doing
Whether those are optimized (using the right indexes, mainly?), using the EXPLAIN instruction, if you are using MySQL
See also: Optimizing SELECT and Other Statements
You can, for instance, activate log_slow_queries to get a list of the requests that take "too much" time, and start your optimization by those.
whether you could cache some of these queries (see what I said earlier)
Is your MySQL well configured? I don't know much about that, but there are some configuration options that might have some impact.
Optimizing the MySQL Server might give you some interesting informations about that.
Still, the two most important things are:
Don't go to the DB if you don't need to: cache as much as you can!
When you have to go to the DB, use efficient queries: use indexes; and profile!
And what now?
If you are still reading, what else could be optimized?
Well, there is still room for improvements... A couple of architecture-oriented ideas might be:
Switch to an n-tier architecture:
Put MySQL on another server (2-tier: one for PHP; the other for MySQL)
Use several PHP servers (and load-balance the users between those)
Use another machines for static files, with a lighter webserver, like:
lighttpd
or nginx -- this one is becoming more and more popular, btw.
Use several servers for MySQL, several servers for PHP, and several reverse-proxies in front of those
Of course: install memcached daemons on whatever server has any amount of free RAM, and use them to cache as much as you can / makes sense.
Use something "more efficient" that Apache?
I hear more and more often about nginx, which is supposed to be great when it comes to PHP and high-volume websites; I've never used it myself, but you might find some interesting articles about it on the net;
for instance, PHP performance III -- Running nginx.
See also: PHP-FPM - FastCGI Process Manager, which is bundled with PHP >= 5.3.3, and does wonders with nginx.
Well, maybe some of those ideas are a bit overkill in your situation ^^
But, still... Why not study them a bit, just in case ? ;-)
And what about Kohana?
Your initial question was about optimizing an application that uses Kohana... Well, I've posted some ideas that are true for any PHP application... Which means they are true for Kohana too ;-)
(Even if not specific to it ^^)
I said: use cache; Kohana seems to support some caching stuff (You talked about it yourself, so nothing new here...)
If there is anything that can be done quickly, try it ;-)
I also said you shouldn't do anything that's not necessary; is there anything enabled by default in Kohana that you don't need?
Browsing the net, it seems there is at least something about XSS filtering; do you need that?
Still, here's a couple of links that might be useful:
Kohana General Discussion: Caching?
Community Support: Web Site Optimization: Maximum Website Performance using Kohana
Conclusion?
And, to conclude, a simple thought:
How much will it cost your company to pay you 5 days? -- considering it is a reasonable amount of time to do some great optimizations
How much will it cost your company to buy (pay for?) a second server, and its maintenance?
What if you have to scale larger?
How much will it cost to spend 10 days? more? optimizing every possible bit of your application?
And how much for a couple more servers?
I'm not saying you shouldn't optimize: you definitely should!
But go for "quick" optimizations that will get you big rewards first: using some opcode cache might help you get between 10 and 50 percent off your server's CPU-load... And it takes only a couple of minutes to set up ;-) On the other side, spending 3 days for 2 percent...
Oh, and, btw: before doing anything: put some monitoring stuff in place, so you know what improvements have been made, and how!
Without monitoring, you will have no idea of the effect of what you did... Not even if it's a real optimization or not!
For instance, you could use something like RRDtool + cacti.
And showing your boss some nice graphics with a 40% CPU-load drop is always great ;-)
Anyway, and to really conclude: have fun!
(Yes, optimizing is fun!)
(Ergh, I didn't think I would write that much... Hope at least some parts of this are useful... And I should remember this answer: might be useful some other times...)
Use XDebug and WinCacheGrind or WebCacheGrind to profile and analyze slow code execution.
(source: jokke.dk)
Profile code with XDebug.
Use a lot of caching. If your pages are relatively static, then reverse proxy might be the best way to do it.
Kohana is out of the box very very fast, except for the use of database objects. To quote Zombor "You can reduce memory usage by ensuring you are using the database result object instead of result arrays." This makes a HUGEE performance difference on a site that is being slammed. Not only does it use more memory, it slows down execution of scripts.
Also - you must use caching. I prefer memcache and use it in my models like this:
public function get($e_id)
{
$event_data = $this->cache->get('event_get_'.$e_id.Kohana::config('config.site_domain'));
if ($event_data === NULL)
{
$this->db_slave
->select('e_id,e_name')
->from('Events')
->where('e_id', $e_id);
$result = $this->db_slave->get();
$event_data = ($result->count() ==1)? $result->current() : FALSE;
$this->cache->set('event_get_'.$e_id.Kohana::config('config.site_domain'), $event_data, NULL, 300); // 5 minutes
}
return $event_data;
}
This will also dramatically increase performance. The above two techniques improved a sites performance by 80%.
If you gave some more information about where you think the bottleneck is, I'm sure we could give some better ideas.
Also check out yslow (google it) for some other performance tips.
Strictly related to Kohana (you probably already have done this, or not):
In production mode:
Enable internal caching (this will only cache the Kohana::find_file results, but this actually can help a lot.
Disable profiler
Just my 2 cents :)
I totally agree with the XDebug and caching answers. Don't look into the Kohana layer for optimization until you've identified your biggest speed and scale bottlenecks.
XDebug will tell you were you spend the most of your time and identify 'hotspots' in your code. Keep this profiling information so you can baseline and measure performance improvements.
Example problem and solution:
If you find that you're building up expensive objects from the database each time, that don't really change often, then you can look at caching them with memcached or another mechanism. All of these performance fixes take time and add complexity to your system, so be sure of your bottlenecks before you start fixing them.