How to keep XSLs in Memory?

[Alexis]

Hello,

I'm working on a project that uses over a hundred XLSs for transforming xml
documents. The project consists of several webservices (IIS) calling a few
dlls. This dlls make the business logic and are the ones that do the
transformation, so the XLSs are used by these dlls. Right now we have the
XSLs files on hard disk. This means there is lots of reading from disk. Since
reading from disk is much slower than reading from memory I am looking for a
way to keep them in memory.
Any Ideas?
Will IIS cache them? How? (Keep in mind they are used by the dlls)

I also was thinking simple work around. Using a RAM Disk, but it seems
Windows 2003 server does not support RAM Disks.

Any help?

Thanks.

[Alexis]

I am not really a fan of using third-party software but thanks any way for
the tip.

"Ross Presser" wrote:

On Mon, 21 Mar 2005 06:59:04 -0800, Alexis wrote:

I also was thinking simple work around. Using a RAM Disk, but it seems
Windows 2003 server does not support RAM Disks.

There's no RAM disk driver *shipped* with Windows 2000 and above, but there
are many third-party RAM disk drivers available that will work. Seek (on
Google) and ye shall find.

[Ross Presser]

On Thu, 24 Mar 2005 07:07:03 -0800, Alexis wrote:

I have not have time to try it yet but it make a lot of sense. I was just
wondering how efficient it may be. The whole purpose of keeping the XSL files
or objects in memory is to improve performance. Do you know if accessing the
HttpContext from a dll will have some impact on performance?

Well, the thing of it is, where do you expect the DLL to cache it? You need
something that has persistence between invocations of your DLL, and the
easiest answer to that is to let ASP.NET handle it. And the way to access
ASP.NET's cache is through HttpContext.Cur rent.

I could be wrong about this, and you might want to check the other dotnet
newsgroups for a more informed opinion.

[Alexis]

What I want to keep in memory are XSLs files used for transformation not the
data so the contenct don't change, but I don't think ASP.NET will cache XSL
files. See my original goal is to keep XSL files in memory instead of having
to read them from disk on every request

"Ross Presser" wrote:

On Thu, 24 Mar 2005 07:07:03 -0800, Alexis wrote:

I have not have time to try it yet but it make a lot of sense. I was just
wondering how efficient it may be. The whole purpose of keeping the XSL files
or objects in memory is to improve performance. Do you know if accessing the
HttpContext from a dll will have some impact on performance?

Well, the thing of it is, where do you expect the DLL to cache it? You need
something that has persistence between invocations of your DLL, and the
easiest answer to that is to let ASP.NET handle it. And the way to access
ASP.NET's cache is through HttpContext.Cur rent.

I could be wrong about this, and you might want to check the other dotnet
newsgroups for a more informed opinion.

[Ross Presser]

On Fri, 25 Mar 2005 07:27:03 -0800, Alexis wrote:

What I want to keep in memory are XSLs files used for transformation not the
data so the contenct don't change, but I don't think ASP.NET will cache XSL
files. See my original goal is to keep XSL files in memory instead of having
to read them from disk on every request

ASP.NET's Application object, or Cache object, will cache ANY object, with
whatever expiration/retention rules you care to set up.

[Alexis]

I would like to try to cache the xsl objects them.
Can you provide me with a code sample? I have not used cahing in yet.

"Ross Presser" wrote:

On Fri, 25 Mar 2005 07:27:03 -0800, Alexis wrote:

What I want to keep in memory are XSLs files used for transformation not the
data so the contenct don't change, but I don't think ASP.NET will cache XSL
files. See my original goal is to keep XSL files in memory instead of having
to read them from disk on every request

ASP.NET's Application object, or Cache object, will cache ANY object, with
whatever expiration/retention rules you care to set up.

[Ross Presser]

On Wed, 30 Mar 2005 07:05:07 -0800, Alexis wrote:

I would like to try to cache the xsl objects them.
Can you provide me with a code sample? I have not used cahing in yet.

Hope you don't mind VB.NET ...

' this function will look in the ASP.NET cache for an XSLTransform;
' if it's there, it will return it;
' if it's not, it will call CreateTheXSLT() to create it.
Public Function GetXSLTObject(B yVal key As String) _
As System.Xml.Xsl. XslTransform
' get a handle to the ASP.NET cache
Dim c As Web.Caching.Cac he
c = HttpContext.Cur rent.Cache

Dim x As System.Xml.Xsl. XslTransform
If c.Item(key) Is Nothing Then
' it wasn't in the cache ...
' create it fresh, then put it in the cache
x = CreateTheXSLT(k ey)
' sliding expiration of 2 hrs ...
' if we don't use it for 2 hrs, ASP.NET is allowed to
' purge it from the cache
c.Add(key, x, Nothing, Nothing, _
System.TimeSpan .FromHours(2), _
Caching.CacheIt emPriority.Norm al, _
Nothing)
Return x
Else
' yaay, it was in the cache ... return it
x = c.Item(key)
Return x
End If

End Function