Speed Up The Web Part III

Speed Up The Web Part III

Posted:  June 1, 2012

Speed Up The Web Part III

Boy oh boy, it’s about time we go another one of these “Speed Up The Web” articles out here.

As with our last article we showed you how you can develop your ASP.Net website and automatically concatenate your scripts and stylesheets. This article will show you a nice and easy caching mechanism for all your static content. This of course, assumes you do not have use of a CDN (Content Delivery Network).

Now here we have built ourselves a CDN, and for the purposes of this article, we are going to show you how we achieved the caching, and gzipping utilized throughout it.

First and foremost, let’s get the obvious out of the way first:

  • What Is Caching?
  • What Is GZipping?

What Is Caching?

Caching is the temporary storage of frequently accessed data in higher speed media (typically SRAM or RAM) for more efficient retrieval. Web caching stores frequently used objects closer to the client through browser, proxy, or server caches. By storing “fresh” objects closer to your users, you avoid round trips to the origin server, reducing bandwidth consumption, server load, and most importantly, latency.

Caching is not just for static sites, even dynamic sites can benefit from caching. Graphics and multimedia typically don’t change as frequently as (X)HTML files. Graphics that seldom change like logos, headers, and navigation can be given longer expiration times while resources that change more frequently like XHTML and XML files can be given shorter expiration times. By designing your site with caching in mind, you can target different classes of resources to give them different expiration times with only a few lines of code.

Client Caching

Client caching of web sites refers to the storage of CSS, Scripts, Images, HTML, etc on the computer of the person browsing the website.  For the most part this is an extremely efficient method for getting your site to load really fast, by loading these files from their local computer instead of having to download them from the server again.

What happens if the content on the page changes?  Well, other bits of data are sent along the path of the request to the web page you are visiting.  These are called headers, and certain headers can specify if the page, or resource has been changed recently, or even set expiration dates/times for said content.   This will allow client web browsers to download updated versions as they happen.

Proxy Caching

Web proxy caching enables you to store copies of frequently-accessed web objects (such as documents, images, and articles) off server, and then serve this information to users on demand. It improves server performance and frees up network bandwidth to the server for other tasks.

Server Caching

Server caching directly refers to the storage of static/dynamic data in the server memory or hard disk, rather than in the clients web browser’s internal cache.  This usually is just an internal method to cache data for a web application, for example, data is pulled from a database, if this data is unchanged, then there is no need to pull it again, so we store it in the server cache and simply pull it from there.

What Is GZipping?

Gzipping refers to the method of compressing and un-compressing static content sent to the client’s web browser.  Files like minified javascripts, minified css stylesheets, some fonts all benefit greatly from this.  By making the files to send smaller, there is less network traffic when a browser requests a web page.


Now that we got all the nitty gritty details out of the way, how about some code for how we do it?  This is by no means the 100% way to do it, but it is what we have found that works the best for us, and our applications (and I am sure there could be improvements).  Especially our CDN 🙂

This is all done in .Net, and really only consists of a couple classes in our CA.  The main work is done in our web.config file.  So, without any further ado…  here’s the code:

Web.Config

<?xml version="1.0"?>
<configuration>
  <system.runtime.caching>
    <memoryCache>
      <namedCaches>
        <add name="default" cacheMemoryLimitMegabytes="0" physicalMemoryLimitPercentage="25" pollingInterval="00:02:00"/>
      </namedCaches>
    </memoryCache>
  </system.runtime.caching>
  <system.web>
    <pages validateRequest="false" buffer="true"/>
    <httpRuntime executionTimeout="360"
                 maxRequestLength="102400"
                 useFullyQualifiedRedirectUrl="false"
                 minFreeThreads="8"
                 minLocalRequestFreeThreads="4"
                 appRequestQueueLimit="100"
                 requestValidationMode="2.0"
                 enableKernelOutputCache="false"/>
    <customErrors mode="Off"/>
    <compilation debug="false" strict="false" explicit="true" targetFramework="4.0"/>
    <httpHandlers>
      <add verb="GET" path="*.*" validate="false" type="CA.ProcessAsync"/>
    </httpHandlers>
  </system.web>
  <system.webServer>
    <validation validateIntegratedModeConfiguration="false"/>
    <modules runAllManagedModulesForAllRequests="true"/>
    <handlers>
      <add name="all" verb="GET" path="*.*" type="CA.ProcessAsync" preCondition="integratedMode"/>
    </handlers>
  </system.webServer>
</configuration>

ProcessAsync.vb

Imports System.Threading.Tasks
Imports System.Web

Public Class ProcessAsync
    Implements IHttpAsyncHandler

    Private Sub DoIt(ByVal context As HttpContext)
        Try
            Dim _file As String, _name As String, _ext As String
            _file = context.Server.MapPath(context.Request.FilePath.Replace(".ashx", ""))
            _name = _file.Substring(_file.LastIndexOf("") + 1)
            _ext = _file.Substring(_file.LastIndexOf(".") + 1)
            With context.Response
                If _ext.Equals("aspx") Then
                    Dim handler As Web.IHttpHandler = UI.PageParser.GetCompiledPageInstance(context.Request.Path,
                                                                                            context.Request.PhysicalPath,
                                                                                            context)
                    context.Server.Transfer(handler, True)
                Else
                    .ClearHeaders()
                    .AddHeader("Powered By", "o7t.In ~ o7th Web Design")
                    Parallel.Invoke(Sub()
                                        Select Case _ext
                                            Case "png", "jpg", "jpe", "jpeg", "tif", "tiff", "gif", "bmp",
                                                "cur", "ico",
                                                "pdf", "swf",
                                                "woff"
                                            Case Else
                                                Common.GZipOutput(context)
                                        End Select
                                    End Sub,
                                    Sub()
                                        Common.SetBrowserCache(context)
                                    End Sub,
                                    Sub()
                                        .ContentType = Common.SetContentType(_ext)
                                    End Sub,
                                    Sub()
                                        .AddHeader("Content-Disposition", "inline; filename=" & _name)
                                    End Sub)
                    .WriteFile(_file)
                End If
            End With
        Catch ex As Exception
        End Try
    End Sub

    Private _Delegate As AsyncProcessorDelegate
    Protected Delegate Sub AsyncProcessorDelegate(context As HttpContext)

    Public Function BeginProcessRequest(ByVal context As HttpContext, ByVal cb As AsyncCallback, ByVal extraData As Object) As IAsyncResult Implements IHttpAsyncHandler.BeginProcessRequest
        _Delegate = New AsyncProcessorDelegate(AddressOf ProcessRequest)
        Return _Delegate.BeginInvoke(context, cb, extraData)
    End Function

    Public Sub EndProcessRequest(ByVal result As IAsyncResult) Implements IHttpAsyncHandler.EndProcessRequest
        _Delegate.EndInvoke(result)
    End Sub

    Public ReadOnly Property IsReusable() As Boolean Implements IHttpHandler.IsReusable
        Get
            Return True
        End Get
    End Property

    Public Sub ProcessRequest(ByVal context As HttpContext) Implements IHttpHandler.ProcessRequest
        DoIt(context)
    End Sub

End Class

Common.vb

Public Class Common

    Public Shared Sub GZipOutput(ByVal context As Web.HttpContext)
        With context
            If IsGZipSupported(context) Then
                Dim accEncoding As String
                accEncoding = .Request.Headers("Accept-Encoding")
                If accEncoding.Contains("gzip") Then
                    .Response.Filter = New System.IO.Compression.GZipStream(.Response.Filter, System.IO.Compression.CompressionMode.Compress)
                    .Response.AppendHeader("Content-Encoding", "gzip")
                Else
                    .Response.Filter = New System.IO.Compression.DeflateStream(.Response.Filter, System.IO.Compression.CompressionMode.Compress)
                    .Response.AppendHeader("Content-Encoding", "deflate")
                End If
            End If
        End With
    End Sub

    Public Shared Sub SetBrowserCache(ByVal context As Web.HttpContext)
        With context.Response
            .AddHeader("Cache-Control", "store, cache")
            .AddHeader("Pragma", "cache")
            .AddHeader("Cache-Control", "max-age=21600")
            .AddHeader("ETag", Date.Now.Ticks)
            .AddHeader("Expires", DateTime.Now.AddYears(1).ToString("ddd, dd MMM yyyy hh:mm:ss") + " GMT")
            .AddHeader("Vary", "Accept-Encoding")
            .Cache.SetVaryByCustom("Accept-Encoding")
            .Cache.SetOmitVaryStar(True)
            .Cache.VaryByParams.IgnoreParams = True
            .Cache.SetAllowResponseInBrowserHistory(True)
            .Cache.SetCacheability(Web.HttpCacheability.Public)
            .Cache.SetValidUntilExpires(True)
            .Cache.SetLastModified(DateTime.Now.AddYears(-1).ToString("ddd, dd MMM yyyy hh:mm:ss") + " GMT")
            .CacheControl = "public" '
            .Expires = 24 * 60 * 366
            .ExpiresAbsolute = DateTime.Now.AddYears(1).ToString("ddd, dd MMM yyyy hh:mm:ss") + " GMT"
        End With
    End Sub

    Public Shared Function SetContentType(ByVal _Ext As String) As String
        Select Case _Ext
            Case "pdf"
                Return "application/pdf"
            Case "rdf"
                Return "application/rdf+xml"
            Case "svg"
                Return "image/svg+xml"
            Case "tif", "tiff"
                Return "image/tiff"
            Case "swf"
                Return "application/x-shockwave-flash"
            Case "png"
                Return "image/png"
            Case "jpg", "jpe", "jpeg"
                Return "image/jpg"
            Case "gif"
                Return "image/gif"
            Case "bmp"
                Return "image/bmp"
            Case "css"
                Return "text/css"
            Case "js"
                Return "text/js"
            Case "atom"
                Return "application/atom+xml"
            Case "xml", "dtd", "xls", "config"
                Return "application/xml"
            Case "txt", "asc"
                Return "text/plain"
            Case "htm", "html", "shtml"
                Return "text/html"
            Case "xhtml", "xht"
                Return "application/xhtml+xml"
            Case "cur"
                Return "image/x-win-bitmap"
            Case "ico"
                Return "image/vnd.microsoft.icon"
            Case "eot"
                Return "application/vnd.ms-fontobject"
            Case "woff"
                Return "application/x-font-woff"
            Case "otf", "ttf"
                Return "application/octet-stream"
            Case Else
                Return "text/html"
        End Select
    End Function

    Private Shared Function IsGZipSupported(ByVal _Context As Web.HttpContext) As Boolean
        Dim accEncoding As String = _Context.Request.Headers("Accept-Encoding")
        If (Not accEncoding Is Nothing) Then
            If (accEncoding.Contains("gzip") Or accEncoding.Contains("deflate")) Then
                Return True
            Else
                Return False
            End If
        Else
            Return False
        End If
    End Function

End Class

Enjoy folks, and thanks for reading!

Kevin Pirnie

Kevin Pirnie

20+ Years of PC and server maintenance & over 15+ years of web development/design experience; you can rest assured that I take every measure possible to ensure your computers are running to their peak potentials. I treat them as if they were mine, and I am quite a stickler about keeping my machines up to date and optimized to run as well as they can.

Our Privacy Policy

Revised: June 8, 2021

Thank you for choosing to be part of my website at https://kevinpirnie.com (“Company”, “I”, “me”, “mine”). I am committed to protecting your personal information and your right to privacy. If you have any questions or concerns about this privacy notice, or my practices with regards to your personal information, please contact me at .

When you visit my website https://kevinpirnie.com (the “Website”), and more generally, use any of my services (the “Services”, which include the Website), I appreciate that you are trusting me with your personal information. I take your privacy very seriously. In this privacy notice, I seek to explain to you in the clearest way possible what information we collect, how I use it and what rights you have in relation to it. I hope you take some time to read through it carefully, as it is important. If there are any terms in this privacy notice that you do not agree with, please discontinue use of my Services immediately.

This privacy notice applies to all information collected through my Services (which, as described above, includes our Website), as well as, any related services, sales, marketing or events.

Please read this privacy notice carefully as it will help you understand what I do with the information that I collect.

1. WHAT INFORMATION DO I COLLECT?

Information automatically collected

In Short: Some information – such as your Internet Protocol (IP) address and/or browser and device characteristics – is collected automatically when you visit my Website.

I automatically collect certain information when you visit, use or navigate the Website. This information does not reveal your specific identity (like your name or contact information) but may include device and usage information, such as your IP address, browser and device characteristics, operating system, language preferences, referring URLs, device name, country, location, information about how and when you use our Website and other technical information. This information is primarily needed to maintain the security and operation of our Website, and for our internal analytics and reporting purposes.

Like many businesses, I also collect information through cookies and similar technologies.

The information I collect includes:
Log and Usage Data. Log and usage data is service-related, diagnostic, usage and performance information our servers automatically collect when you access or use our Website and which we record in log files. Depending on how you interact with us, this log data may include your IP address, device information, browser type and settings and information about your activity in the Website (such as the date/time stamps associated with your usage, pages and files viewed, searches and other actions you take such as which features you use), device event information (such as system activity, error reports (sometimes called ‘crash dumps’) and hardware settings).

Device Data. I collect device data such as information about your computer, phone, tablet or other device you use to access the Website. Depending on the device used, this device data may include information such as your IP address (or proxy server), device and application identification numbers, location, browser type, hardware model Internet service provider and/or mobile carrier, operating system and system configuration information.

Location Data. I collect location data such as information about your device’s location, which can be either precise or imprecise. How much information I collect depends on the type and settings of the device you use to access the Website. For example, I may use GPS and other technologies to collect geolocation data that tells me your current location (based on your IP address). You can opt out of allowing me to collect this information either by refusing access to the information or by disabling your Location setting on your device. Note however, if you choose to opt out, you may not be able to use certain aspects of the Services.

2. HOW DO I USE YOUR INFORMATION?

In Short: I process your information for purposes based on legitimate business interests, the fulfillment of my contract with you, compliance with my legal obligations, and/or your consent.

I use personal information collected via my Website for a variety of business purposes described below. I process your personal information for these purposes in reliance on my legitimate business interests, in order to enter into or perform a contract with you, with your consent, and/or for compliance with my legal obligations. I indicate the specific processing grounds I rely on next to each purpose listed below.

For other business purposes. I may use your information for other business purposes, such as data analysis, identifying usage trends, determining the effectiveness of our promotional campaigns and to evaluate and improve my Website, products, marketing and your experience. I may use and store this information in aggregated and anonymized form so that it is not associated with individual end users and does not include personal information. I will not use identifiable personal information without your consent.

3. WILL YOUR INFORMATION BE SHARED WITH ANYONE?

In Short: I only share information with your consent, to comply with laws, to provide you with services, to protect your rights, or to fulfill business obligations.

4. DO WE USE COOKIES AND OTHER TRACKING TECHNOLOGIES?

In Short: I may use cookies and other tracking technologies to collect and store your information.

I may use cookies and similar tracking technologies (like web beacons and pixels) to access or store information. Specific information about how I use such technologies and how you can refuse certain cookies is set out in our Cookie Notice.

5. IS YOUR INFORMATION TRANSFERRED INTERNATIONALLY?

In Short: We may transfer, store, and process your information in countries other than your own.

My servers are located in the United States of America, unless otherwise requested by my clients. If you are accessing my Website from outside, please be aware that your information may be transferred to, stored, and processed by me in my facilities and by those third parties with whom I may share your personal information (see “WILL YOUR INFORMATION BE SHARED WITH ANYONE?” above), in and other countries.

If you are a resident in the European Economic Area, then these countries may not necessarily have data protection laws or other similar laws as comprehensive as those in your country. I will however take all necessary measures to protect your personal information in accordance with this privacy notice and applicable law.

6. HOW LONG DO WE KEEP YOUR INFORMATION?

In Short: I keep your information for as long as necessary to fulfill the purposes outlined in this privacy notice unless otherwise required by law.

I will only keep your personal information for as long as it is necessary for the purposes set out in this privacy notice, unless a longer retention period is required or permitted by law (such as tax, accounting or other legal requirements). No purpose in this notice will require me keeping your personal information for longer than 6 months.

When I have no ongoing legitimate business need to process your personal information, I will either delete or anonymize such information, or, if this is not possible (for example, because your personal information has been stored in backup archives), then I will securely store your personal information and isolate it from any further processing until deletion is possible.

7. HOW DO WE KEEP YOUR INFORMATION SAFE?

In Short: I aim to protect your personal information through a system of organizational and technical security measures.

I have implemented appropriate technical and organizational security measures designed to protect the security of any personal information I process. However, despite our safeguards and efforts to secure your information, no electronic transmission over the Internet or information storage technology can be guaranteed to be 100% secure, so I cannot promise or guarantee that hackers, cybercriminals, or other unauthorized third parties will not be able to defeat my security, and improperly collect, access, steal, or modify your information. Although I will do my best to protect your personal information, transmission of personal information to and from my Website is at your own risk. You should only access the Website within a secure environment.

8. DO WE COLLECT INFORMATION FROM MINORS?

In Short: I do not knowingly collect data from or market to children under 18 years of age.

I do not knowingly solicit data from or market to children under 18 years of age. By using the Website, you represent that you are at least 18 or that you are the parent or guardian of such a minor and consent to such minor dependent’s use of the Website. If I learn that personal information from users less than 18 years of age has been collected, I will deactivate the account and take reasonable measures to promptly delete such data from my records. If you become aware of any data I may have collected from children under age 18, please contact me at .

9. WHAT ARE YOUR PRIVACY RIGHTS?

In Short: You may review, change, or terminate your account at any time.

If you are a resident in the European Economic Area and you believe I am unlawfully processing your personal information, you also have the right to complain to your local data protection supervisory authority. You can find their contact details here: http://ec.europa.eu/justice/data-protection/bodies/authorities/index_en.htm.

If you are a resident in Switzerland, the contact details for the data protection authorities are available here: http://ec.europa.eu/justice/data-protection/bodies/authorities/index_en.htm.

Cookies and similar technologies: Most Web browsers are set to accept cookies by default. If you prefer, you can usually choose to set your browser to remove cookies and to reject cookies. If you choose to remove cookies or reject cookies, this could affect certain features or services of my Website.

10. CONTROLS FOR DO-NOT-TRACK FEATURES

Most web browsers and some mobile operating systems and mobile applications include a Do-Not-Track (“DNT”) feature or setting you can activate to signal your privacy preference not to have data about your online browsing activities monitored and collected. At this stage no uniform technology standard for recognizing and implementing DNT signals has been finalized. As such, I do not currently respond to DNT browser signals or any other mechanism that automatically communicates your choice not to be tracked online. If a standard for online tracking is adopted that I must follow in the future, I will inform you about that practice in a revised version of this privacy notice.

11. DO CALIFORNIA RESIDENTS HAVE SPECIFIC PRIVACY RIGHTS?

In Short: Yes, if you are a resident of California, you are granted specific rights regarding access to your personal information.

California Civil Code Section 1798.83, also known as the “Shine The Light” law, permits my users who are California residents to request and obtain from me, once a year and free of charge, information about categories of personal information (if any) I disclosed to third parties for direct marketing purposes and the names and addresses of all third parties with which I shared personal information in the immediately preceding calendar year. If you are a California resident and would like to make such a request, please submit your request in writing to me using the contact information provided below.

If you are under 18 years of age, reside in California, and have a registered account with the Website, you have the right to request removal of unwanted data that you publicly post on the Website. To request removal of such data, please contact us using the contact information provided below, and include the email address associated with your account and a statement that you reside in California. I will make sure the data is not publicly displayed on the Website, but please be aware that the data may not be completely or comprehensively removed from all my systems (e.g. backups, etc.).

12. DO I MAKE UPDATES TO THIS NOTICE?

In Short: Yes, I will update this notice as necessary to stay compliant with relevant laws.

I may update this privacy notice from time to time. The updated version will be indicated by an updated “Revised” date and the updated version will be effective as soon as it is accessible. If I make material changes to this privacy notice, I may notify you either by prominently posting a notice of such changes or by directly sending you a notification. We encourage you to review this privacy notice frequently to be informed of how I am protecting your information.

13. HOW CAN YOU CONTACT ME ABOUT THIS NOTICE?

If you have questions or comments about this notice, you may email me at or by post to:

Kevin C. Pirnie

22 Orlando St.
Feeding Hills, MA 01030
United States of America

14. HOW CAN YOU REVIEW, UPDATE, OR DELETE THE DATA I COLLECT FROM YOU?

Based on the applicable laws of your country, you may have the right to request access to the personal information I collect from you, change that information, or delete it in some circumstances. To request to review, update, or delete your personal information, you may email me at or by post to:

Kevin C. Pirnie

22 Orlando St.
Feeding Hills, MA 01030
United States of America