Generating SSRS through website, fine -- through Code, out of Memory

I have a report that is 68,000 pages plus that needs to be generated in PDF. (I put the comma in so you knew it wasn’t a typo :) And this actually works fine if I generate it through the Website/WebService of SSRS. It takes a little over a minute and generates the first page. During this time Server CPU goes to 100% and Memory to 2GB. After the first page is generated both CPU and Memory drop down to their pre-report state. Now if I choose to export to PDF. CPU on the Server goes to 100 but Memory does not jump significantly maybe .05GB (50 MB) as the pdf is being generated. This takes about 10-15 Minutes.

Now if I use the Render method in code

rs.Render(Me.ReportName, Me.ContentType, Nothing, Nothing, ....

I set the rs.Timeout to 1800000 //(30 minutes). CPU and Memory on the server spikes and about after 10 Minutes I get a out of Memory Exception. I believe from the server and not the host machine with the calling code (a web service).

Now I did notice when the PDF gets render through the SSRS website it creates a new URL with the parameters

ReportSession=gvrjxt4504wtpkiydu0o51fo
ControlID=5754f0889fb34bea80e7b5e97c120cfd
C开发者_开发技巧ulture=1033
UICulture=9
ReportStack=1
OpType=Export
FileName=Invoice+Session+Register+Batch
ContentDisposition=OnlyHtmlInline
Format=PDF

Now it is my belief that it is this ReportSession or ControlId that makes the PDF generation not take up so much memory.

Either way my question is how can I mimic through code the behavior that the Website is showing?

I about to look into LoadReport method and also NULL is one of the content types you can pass to the render method. But I cannot find an example nor and explanation of what it does.

So before I go down all these rabbit holes, has anyone else done something like this or encounter a project like this?

Background:If I generate the report one page at a time it took 9.5 hours to run and generate all the PDFs. I was really excited when I could generate the whole report in 10 minutes and use PDFSharp to split the report. Now I most likely can generate 10,000 or 20,000 at a time but it really fustrates me when a method works but I cannot duplicate it in code.