How many user can enter a site at a time in IIS?
Say, the limit is 100.
Does it mean that 100 user each having various number of request can enter a site?
or
100 user each having a single request can enter a site?
or
100 request are allowed, doesn't matter whether they are from 100 user or not.
Total requests to the server so 100 users at one time.
Controls the number of simultaneous HTTP connections (and hence limits number of simultaneous connections serviceable by IIS6).
•On Windows Server 2003 RTM x86, this comes out to around 8,700
•On Windows Server 2003 SP1, the limit has been removed
•On Windows Server 2003 SP1 x64, since NPP is bound by available memory, you can increase concurrent connections by merely adding more RAM. To give a sense of scope - I have seen 50K+ concurrent connections to IIS6 on WS03SP1 x64 with 4GB RAM
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\HTTP\Parameters
Type: DWORD
Value: Range from 0 to 2^32-1
Why do you have it set so low?
What IIS are you using?
Related
One of our customers has set the application pool to throttle under load at 35%, and at times they noticed the following event
Event ID: 5210
CPU time for application pool 'abc' has been throttled.
They noticed such events show up in the event viewer log, even though the CPU utilization on the web server is not pegged high, for example < 60%
Would like to know:
• Under what condition does the event id 5210 get generated?
• How does IIS detect contention on the CPU? Is it based on a performance counter etc?
The cause of the issue is there is something misconfiguration with your Application Pool.
open iis manager.
Right-click on the appropriate Application Pool and click Advanced Settings.
Set the Limit to 0 and Limit Action value to NoAction.
IIS 8.0 CPU Throttling: Sand-boxing Sites and Applications
This is strange question: you said you had set AppPool to ThrottleUnderLoad and set Limit to 35%. Why do you wonder when it hits the limit and generates a log record? The most common value for the throttle limit is 80%, which allows to throttle the load a little when there are too many requests and the CPU resources are not enough. I don't see sense to set the limit to 35%, this will slow web responses from your server when it has plenty of CPU time.
I suggest increasing the value. This would decrease the number of 5210 warnings.
How many concurrent requests can be executed in IIS 8.5?
I could not find proper values for how many concurrent requests can be executed in IIS 8.5
As I found out below 2 different values:
By default IIS 8.5 can handle 5000 concurrent requests as per MaxConcurrentRequestsPerCPU settings in aspnet.config
In machine.config, the maxconnection is 2 per CPU as default. So if have 6 core CPU then 12 concurrent requests are possible by default.
So I would like to know that Point 1 is right or Point 2 is right for concurrent requests for IIS 8.5.
Assuming that you are using ASP.NET application, the concurrent requests executed can vary based on the way the application code is written and the framework version you are using to run the application (2.0, 3.5, 4+ etc). Also you are confusing with max connect with concurrent requests. Both are two different things.
For more detailed understanding please read msdn blog ASP.NET Thread Usage on IIS 7.5, IIS 7.0, and IIS 6.0 .
To summarize
MaxConcurrentRequestsPerCPU in
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\ASP.NET\2.0.50727.0 determines the number of concurrent requests per CPU. By default, it does not exist and the number of requests per CPU is limited to 12
If your asp.net application is written entirely with asynchronous requests, the default MaxConcurrentReqeustsPerCPU limit of 12 is less and increase this setting MaxConcurrentRequestsPerCPU to a very high number.
In v4.0, the default for MaxConcurrentRequestsPerCPU to 5000
Maxconnection is the setting per HTTP protocol.Any application can only make two concurrent requests to any server.e.g. Your browser(IE 6,7) can make only two connection to your www.example.com. But for speed improvement ,many of the browsers currently make more than 6 simultaneous connections (vary in Chrome, Firefox and IE). Similarly when your server application make a request to a web service or a rest API, the client is your application and maxconnection enforces that for the same server (rest end point), you are allowed to make only two connections .
To increase maxconnection in an ASP.NET application, set
System.Net.ServicePointManager.DefaultConnectionLimit programatically,
from Application_Start, E.g. You can set this to Int32.MaxValue
Hope this helps!
According to this article there is also limitations when running on different Windows versions:
https://blogs.iis.net/owscott/windows-8-iis-8-concurrent-requests-limit
Max concurrent requests
Windows 8:
3 requests
Windows 8 Professional:
10 requests
Windows RT:
N/A since IIS does not run on Windows RT
I assumed (and tested on Windows 10 Home Edition) that on 8 and above this limitations still exists.
These 2 properties are not the same as I think you are implying they are.
MaxConcurrentRequestsPerCPU
Controls the number of incoming requests being handled per CPU
maxconnection
Controls the maximum number of outgoing HTTP connections that you can initiate from a client to a specific IP address.
Our ASP.NET app uses a component that is licensed by the number of processor cores. Unfortunately, our customer wants to deploy the app onto a multi-function server (IIS, SQL Server, file server, etc.) that exceeds the number of processor cores for which the customer is licensed: they are allowed four cores but have two processors with four cores each. I configure IIS to use only one processor?
so i tried to set application pools settings
in applicationpool ->advance setting -> process affinity enable =ture
and i have set number of working process =1
after i have checked in tast manager w3wp.exe-> set affinity its all core are selected
where i made error...
thank u
I have 2 GB of RAM and a 1.8 GHz processor. I conduct load testing site using Visual Studio 2012. How to determine the maximum number of virtual users based on the capacity of the computer (RAM and CPU), which will be tested and the width of the Internet channel (8 megabits per second)?
The number of Virtual Users depends only on your tests and on the target web site.
In some tests, a virtual user needs to execute only a simple request whereas in others tests it can invoke multiple pages and services. Sometimes, the target Web Site is simply too slow.
Personnaly, I prefer to use a goal based pattern. It resembles the step pattern but adjusts the user load based on performance counter thresholds versus periodic user load adjustments. So, I generally run load tests with a CPU on the web server between 40% and 60%.
Can someone tell me the maximum number of websites / virtual directories I can host on a single IIS?
Is there's a difference between IIS 6 and IIS 7?
I'd say you should be more worried about server performance and connection limitations that the number of websites you can host.
I'd say your machine will collapse before you are able to max out the number, but I don't believe there is a hard limit.