I don't know if this is right place to ask but I did not saw any better.
Maybe someone with high demand web sites experience can tell me where is factor for concurrent connection to IIS, when it finally give up and fails? I read some time ago that on web there is 10k problem, when any HTTP server on the market cannot handle that. It is to much IMHO for corporate complex web apps with 3 tiers and high MSSQL usage. I have found that this is approximately 1000 connections at the same time, but it still seems like too much. I cannot imagine 1000 CRUD sqls on MSSQL. Usually for single HTTP requsts there is at least 3 sql requests, usually more. So how much connection web app would handle? 100? Seems more likely, but still in my prevoius work, there was application that had hard time providing for few dozens users and abviously they not always requaired server to do something.
Any one has experience with the point when you start to need not 1 but 2 IIS servers?
Primarily lack of knowledge about this topic. Secondly is requirement of new project: it has to be prepared to work on IIS web farm. I know that load balancing make sense with high-load applications. This is the reason for this question. Where is threshold for IIS when you have to switch from 1 web server to 2 or more to maintain high response times under high-load. I suspect this is dependent from complexity of code, so let's assume that it is complex and not optimal. Also I know that IIS and MSSQL have no hardcoded limit of, lets say 101 connections, and when 102 users decide to open page, it's gonna say to him: 'no way dude!' and gonna send HTTP Code - Service Unavailable. But there have be some kind of queue of connections and when this queue will be adding more requests then server can handle it's gonna shut itself down eventually, right?
I don't want to know exact number as it is impossible without proper stress testing of whole environment, but just a factor should be enough. Is it 10? 100? 1000? 10k? I heard about 10k problem before but I don't know if this still an issue with all this xCore xGHz x0GB RAM server as we have now, and sources are dated: http://en.wikipedia.org/wiki/C10k_problem[^]
I suspect this is dependent from complexity of code, so let's assume that it is complex and not optimal.
It's also dependent on the hardware (server and network), some IIS-settings, the "size" of your average file, and the general state of your servers' OS.
But there have be some kind of queue of connections and when this queue will be adding more requests then server can handle it's gonna shut itself down eventually, right?
AFAIK, it doesn't shut down. If the client doesn't get a response within a set time, he'll get a time-out. Just like in a DDOS-attack, so to speak. The server processes what it can, within the limits of it's hardware.
I heard about 10k problem
I didn't, so I'm gonna shut up and hope that some other reader can contribute some insight into the topic.
Bastard Programmer from Hell If you can't read my code, try converting it here[^]
By default IIS7 has a limit of handling 12 concurrent requests per CPU and will queue requests above this limit. If you have some significant web load and many AJAX style requests to your server – this setting maybe very restrictive and it is hard to find out the root of the problem when you server performance is suddenly degraded.
See this post to get the picture how it can cause performance issues on your server.
Some relevant info about asp.net thread usage on IIS7 here:
asp.net thread usage on IIS7 and IIS6
Thomas Marquardt advice is to change this default limit. Recommended settings: “All of this may be a little confusing, but for nearly everyone, my recommendation is that for ASP.NET 2.0 you should use the same settings as the defaults in ASP.NET v4.0; that is, set maxConcurrentRequestsPerCPU = “5000″ and maxConcurrentThreadsPerCPU=”0″.
This is done by adding DWORD MaxConcurrentRequestsPerCPU to the registry under
called MaxConcurrentRequestsPerCPU (DWORD). This key doesn’t exist by default. Or/and in aspnet.config section which overrides registry setting (also doesn’t exist by default) aspnet.config is here on windows 64bit:
I am planning to purchase Windows Server 2012. I want to ask is it possible to have the same server contains two servers (one actual and virtual) or this feature is only available in Enterprise and dataCenter edition? and if it's possible, is it advisable? and what about the performance for both servers if I am going to have Windows Server 2012 running a Dell R720 with two processors?
Enterprise for Mission Critical & Applications Data Warehousing Advanced high availability with AlwaysOn High performance data warehousing with ColumnStore Maximum virtualization (with Software Assurance) Inclusive of Business Intelligence edition's capabilities
Business Intelligence for Premium Self-Service and Corporate
Business Intelligence Rapid data discovery with Power View Corporate and scalable reporting and analytics Data Quality Services and Master Data Services Inclusive of the Standard edition's capabilities
Standard continues to offer basic database, reporting and analytics capabilities
I've used McAfee on Windows Server 2008 R2 ... for five plus years. That's two (complete?) turns of McAfee "development" cycle and although each time they've changed something in their final production interface that managed to knock something out of whack on this system, I've now grown so familiar with readjustment that using it is really easy.
For instance, filtering IPs (comes wth a firewall replacement for the windows native).
There's not a lot of bell and whistle to it ("SAas" with firewall) like say, latest Norton Antivirus (on Vista 32-bit). But at the time, McAfee was the only vendor coming through for 64-bit personal use. So, it's served me well. To date.
Hello Dears, I have a problem with my application within Win server 2008 , when it is work well within Win server 2003 when I try to use my app with win_ser2008 get the following error message: ///////////////////////////////////////////////// Server Error in '/yyy' Application. --------------------------------------------------------------------------------
ORA-00161: طول فرع الحركة 90 غير مشروع (العدد الأقصى المسموح64 ) Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Data.OracleClient.OracleException: ORA-00161: طول فرع الحركة 90 غير مشروع (العدد الأقصى المسموح64 )
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.
I am a little confuse about usage of CAL license. Suppose i have one database Server 2012 and on the other hand i have one application server where around 50 virtual directories which uses the sa user via web.config file to connect database server. My question is how many CALs required to purchase.
The great pleasure in life is doing what people say you cannot do.
I need to invoke e .NET Managed .EXE located on a Webhost (https://..) from client machines. These clients mostly don't have the .net framework installed. Can I do this from (I know very old) VB6? I know it's old, but IT don't want to install .net framework on 600-800 clients for just one app...
Note: the .EXE application updates exchange calendar info using ExchangeWebService.
Probably I will have to create a webservice that does the job, which I can call from VB6. Unfortunatly I am stuck to this. Internally we have .net installed on the web servers (for our intranet) and the clients just are Win 7 / Xp with office installed, some policies even deny access to the "C:\" drive for standard users (not developers)