I have a webserver which has 5k requests per second this overloads my server with the cpu usage  host has 12 CPU and 8GB ram [ almost not in use ]  my httpd-mpm configuration is below :   &lt;IfModule mpm_prefork_module&gt;     StartServers          5     MinSpareServers       5     MaxSpareServers      10     ServerLimit         1000     MaxRequestWorkers   8000     MaxConnectionsPerChild   10000 &lt;/IfModule&gt;  # worker MPM # StartServers: initial number of server processes to start # MinSpareThreads: minimum number of worker threads which are kept spare # MaxSpareThreads: maximum number of worker threads which are kept spare # ThreadsPerChild: constant number of worker threads in each server process # MaxRequestWorkers: maximum number of worker threads # MaxConnectionsPerChild: maximum number of connections a server process serves #                         before terminating &lt;IfModule mpm_worker_module&gt;     StartServers             10     MinSpareThreads         75     MaxSpareThreads        250     ThreadsPerChild         32     MaxRequestWorkers      8000     MaxConnectionsPerChild   10000 &lt;/IfModule&gt;  # event MPM # StartServers: initial number of server processes to start # MinSpareThreads: minimum number of worker threads which are kept spare # MaxSpareThreads: maximum number of worker threads which are kept spare # ThreadsPerChild: constant number of worker threads in each server process # MaxRequestWorkers: maximum number of worker threads # MaxConnectionsPerChild: maximum number of connections a server process serves #                         before terminating &lt;IfModule mpm_event_module&gt;     StartServers             6     MinSpareThreads         32     MaxSpareThreads        128     ThreadsPerChild         64     ServerLimit             32     MaxRequestWorkers     2048     MaxConnectionsPerChild   10000 &lt;/IfModule&gt;  # NetWare MPM # ThreadStackSize: Stack size allocated for each worker thread # StartThreads: Number of worker threads launched at server startup # MinSpareThreads: Minimum number of idle threads, to handle request spikes # MaxSpareThreads: Maximum number of idle threads # MaxThreads: Maximum number of worker threads alive at the same time # MaxConnectionsPerChild: Maximum  number of connections a thread serves. It #                         is recommended that the default value of 0 be set #                         for this directive on NetWare.  This will allow the #                         thread to continue to service requests indefinitely. &lt;IfModule mpm_netware_module&gt;     ThreadStackSize      65536     StartThreads           250     MinSpareThreads         25     MaxSpareThreads        250     MaxThreads            1000     MaxConnectionsPerChild   0 &lt;/IfModule&gt;  # OS/2 MPM # StartServers: Number of server processes to maintain # MinSpareThreads: Minimum number of idle threads per process,  #                  to handle request spikes # MaxSpareThreads: Maximum number of idle threads per process # MaxConnectionsPerChild: Maximum number of connections per server process &lt;IfModule mpm_mpmt_os2_module&gt;     StartServers             2     MinSpareThreads          5     MaxSpareThreads         10     MaxConnectionsPerChild   0 &lt;/IfModule&gt;  # WinNT MPM # ThreadsPerChild: constant number of worker threads in the server process # MaxConnectionsPerChild: maximum number of connections a server process serves &lt;IfModule mpm_winnt_module&gt;     ThreadsPerChild        150     MaxConnectionsPerChild   0 &lt;/IfModule&gt;  # The maximum number of free Kbytes that every allocator is allowed # to hold without calling free(). In threaded MPMs, every thread has its own # allocator. When not set, or when set to zero, the threshold will be set to # unlimited. &lt;IfModule !mpm_netware_module&gt;     MaxMemFree            2048 &lt;/IfModule&gt; &lt;IfModule mpm_netware_module&gt;     MaxMemFree             100 &lt;/IfModule&gt;   and the server is still overloaded   do you have any suggetions? what to check? maybe change any configuration?  thank you!
This is a  about capacity planning for web sites. Related:      What are some recommended tools and methods of capacity planning for web sites and web-applications? Please feel free to describe different tools and techniques for different web-servers, frameworks, etc., as well as best-practices that apply to web servers in general.
New global search doesn't like tags Prove that the square root of a positive integer is either an integer or irrational Is my proof that the square root of a positive integer is either an integer or an irrational number correct?  The proof goes like this:  Suppose an arbitrary number n, where n is non-negative. If $\sqrt{n}$ is an integer, then $\sqrt{n}$ must be rational. Since $\sqrt{n}$ is an integer, we can conclude that n is a square number, that is  for some integer a.  Therefore, if n is a square number, then $\sqrt{n}$ is rational.  Suppose now that n is not a square number, we want to show that the square root of any non-square number is irrational.  We prove by contradiction. That is, we suppose that the square root of any non-square number is rational. So $\sqrt{n} = \frac{a}{b}$, where $a,b \in Z^+, b \neq 0$. We also suppose that $a \neq 0$, otherwise $\frac ab = 0$ , and n will be a square number, which is rational.   Hence $n = \frac {a^2}{b^2}$, so $nb^2 = a^2$.    Suppose $b=1$. Then $\sqrt n = a$ , which shows that n is a square number. So $b \neq 1$. Since $\sqrt n &gt; 1$, then $a&gt;b&gt;1$.  By the unique factorization of integers theorem, every positive integer greater than $1$ can be expressed as the product of its primes.  Therefore, we can write $a$ as a product of primes and for every prime number that exists in $a$, there will be an even number of primes in $a^2$. Similarly, we can express $b$ as a product of primes and for every prime number that exists in $b$, there will be an even number of primes in $b^2$.  However, we can also express $n$ as a product of primes. Since $n$ is not a square number, then there exist at least one prime number that has an odd number of primes.  Therefore, there exists at least one prime in the product of $nb^2$  that has an odd number of primes. Since $nb^2=a^2$ , then this contradicts the fact that there is an even number of primes in $a^2$ since a number can neither be even and odd.  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