Why does Apache have so many processes?
Apache httpd always tries to maintain several spare or idle server processes, which stand ready to serve incoming requests. In this way, clients do not need to wait for a new child processes to be forked before their requests can be served.
Why is Apache using so much memory?
Apache comes with a lot of default settings. And, these default settings can unintentionally become one of the major causes for the high memory usage. Firstly, let’s take a look at the Multi Processing Module (MPM) of Apache. For e.g., By default, most Apache softwares come with Prefork module.
How do I increase Httpd memory?
You can achieve this performance boost by changing a few settings.
- Locate and open the httpd. conf file with a text editor.
- Locate the following settings within the httpd.
- Update the StartServers, MinSpareServers, MaxSpareServers, ServerLimit, MaxClients and MaxRequestsPerChild values.
- Save the httpd.
How much RAM does Apache use?
Most operating systems’ default Apache configurations are not well suited for smaller servers– 25 child processes or more is common. If each of your Apache child processes uses 120MB of RAM, then your VPS would need 3GB just for Apache.
How many requests can Apache handle per second?
160 requests per second
By default, Apache Request limit is 160 requests per second, that is, Apache can handle up to 160 requests per second, without any modification.
What is Apache MPM?
The Apache Web Server comes with a Multi-Processing Modules (MPMs) mainly ‘prefork’ MPM and ‘worker’ MPM which are responsible for binding to network ports on the machine, accepting requests, and dispatching children to handle the requests.
How can I make Apache faster?
Here are top 5 ways to speed up Apache web server.
- Use Apache Latest Version. Every Apache version contains performance improvements that make it faster than previous versions.
- Use Disk based caching.
- Choose the right MPM module.
- Use mod_gzip/mod_deflate modules.
- Do Not set High KeepAliveTimeout.
What is keep alive timeout in Apache?
The keepalive timeout is a timer that counts down, and is reset every time the web browser asks for a new item. So long as the browser keeps asking for more things, the timeout will not expire, even with a keepalive timout setting of 1 second. However, the default setting for Apache Keepalive Timeout is 15 seconds.
Which directive do you use to limit the amount of RAM the Apache server can use?
The MaxClients directive sets the limit on the number of simultaneous requests that can be supported. No more than this number of child server processes will be created. To configure more than 256 clients, you must edit the HARD_SERVER_LIMIT entry in httpd. h and recompile Apache.
How much memory should a Web server have?
Recommended RAM: 512MB to 1GB per site While you can run a small website with as little as 256MB of RAM, if you’re installing WordPress on your own server you’ll want at least 512 MB of RAM for your basic site if you want to ensure good performance.
How does Apache handle multiple requests?
Requests are handled in parallel by the web server (which runs the PHP script). Updating data in the database is pretty fast, so any update will appear instantaneous, even if you need to update multiple tables.
Is Apache multi-threaded?
Apache is multithreaded, this is the only way how the web application server could respond to multiple requests from different clients.
What is the difference between Prefork MPM and worker MPM?
Prefork MPM uses multiple child processes with one thread each and each process handles one connection at a time. Worker MPM uses multiple child processes with many threads each. Each thread handles one connection at a time.
How do I know if Apache Cache is working?
You can check if your apache is really caching content or not by confirming below points.
- check size of /var/cache directory. It should be growing in size after some time when there is hit on your apache.
- You can check in logs, there should response code 302 instead of 200.
How can I improve my httpd performance?
3 ways to improve Apache web server performance
- Update Apache.
- Remove the burden of processing code from Apache.
- Change Apache’s MaxKeepAliveRequests, KeepAlive, and KeepAliveTimeout settings.
How do I increase my Apache server timeout?
Here are the steps to increase request timeout in Apache.
- Open Apache configuration file. Open Apache configuration file in a text editor.
- Increase Request Timeout in Apache. If you want to increase request timeout to 600 seconds, just add the following line to your Apache configuration file.
- Restart Apache Web Server.
Is 2 GB RAM enough web server?
To effectively run a single server online store, whether you build it on your own or use a platform like Magento, you’ll want at least 2GB of RAM. If your website gets millions of views and you handle a large number of transactions, then it’s better to choose a plan with at least 4GB of RAM.
Is 16GB RAM enough for web server?
8GB to 16GB: The sweet spot However, it’s very common for users to run many of these applications at once. Many people also like to open multiple browser tabs at once, and they can access web sites that display a lot of graphics, run various web applications, and play video.
Apache needs to fork a process to handle each connected client. Read more about that here. The upshot is that you have lots of processes because you have lots of connections. If your server is running slowly as a result then here are a few options:
Are the dozens of httpd processes showing on top a DoS attack?
In my experience, the dozens of httpd processes were DOS attacks. After installing mod_evasive, the dozens of httpd processes showing via top were all but eliminated and my mysql CPU load went from an average 100%+ / 99% of the time utilization down to an expected 20% load during heavier query operations. and viola.
How to change the default mode of httpd?
You can change it to the mode of event, worker or prefork (default) in the file 00-mpm.conf, which file path is /etc/httpd/conf.modules.d. Read details of this configure in the above-mentioned reference.
Does MPM prefork work with httpd?
Before, the numbers of httpd processes increased until the system halted. Aftering setting the MPM Prefork, it works fine. Thanks for contributing an answer to Stack Overflow!