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• 01-06-2009, 1:46 AM

  Mike Trader Joined on 10-10-2008, 4:01 PM Posts 25

  FastCGI terminating using POST method Reply Contact  The concept of fast CGi is that the process outlives the request. This is very usefull for situations where a number of requests are required to complete a larger process. In this case, I am uploading a larger file (10MB) in chunks. If I tried to do a single POST I would run into the SndTo  TIMEOUT: I am using WinHTTP (not WinInet) which supports 4 timeout settings: ResolveTO   ' resolving a host name                       ConnectTO  ' establishing a communication socket         SndTo         ' Total running time for sending data         ReceiveTO  ' Total running time for receiving any data   So by breaking the larger file up into 64k chunks I can send them one at a time. Each chunk is a complete HTTP request and response by the client and is serviced by the FastCGI executable. But there is a problem. For some reason, the FastCGI executable is terminated after processing each chunk IF the chunk size is larger than about 2500 bytes (determined experimentally) To test this, I wrote a simple client that issues n WinHTTP POST request's in a row, each with x bytes of POST data. The results are:   --------  01-05-2009  22:28:17  ---------  1 Bytes sent= 4000 FastCGI Reply: Count= 1, ContentLen= 4000  2 Bytes sent= 4000 FastCGI Reply: Count= 1, ContentLen= 4000  3 Bytes sent= 4000 FastCGI Reply: Count= 1, ContentLen= 4000   Notice the Count variable is allwys 1 because the FastCGi termination IS NOT outliving the request. When I lower the number of bytes: --------  01-05-2009  22:42:28  ---------  1 Bytes sent= 2000 FastCGI Reply: Count= 1, ContentLen= 2000  2 Bytes sent= 2000 FastCGI Reply: Count= 2, ContentLen= 2000  3 Bytes sent= 2000 FastCGI Reply: Count= 3, ContentLen= 2000 Now the FastCGI process outlives each request and all is good. The three requests take around 2 secs with my current connection. All the timouts on the server are 10secs or more:  [C:\Inetpub\wwwroot\MyServer\cgi-bin\FCGITest.exa] QueueLength=999 MaxInstances=20 InstanceTimeout=60 InstanceMaxRequests=500 IdleTimeout=10 ActivityTimeout=10 RequestTimeout=10  Is there something simple I have overlooked?   When I increase the Chunk Size to 64k, it still only takes about 3/4 seconds to complete:  --------  01-05-2009  22:58:26  ---------  1 Bytes sent= 64000 FastCGI Reply: Count= 1, ContentLen= 64000  2 Bytes sent= 64000 FastCGI Reply: Count= 1, ContentLen= 64000  3 Bytes sent= 64000 FastCGI Reply: Count= 1, ContentLen= 64000  4 Bytes sent= 64000 FastCGI Reply: Count= 1, ContentLen= 64000 All the data is received ok.

• 01-06-2009, 4:29 AM

  In reply to

  anilr Joined on 05-23-2006, 10:13 PM Redmond, WA Posts 2,343	Re: FastCGI terminating using POST method Reply Contact Why are you making your life difficult by splitting up your upload in this way?  The winhttp timeout is per send and not the total for the request, so you can easily send the entity body in one request without hitting the timeout? Anil Ruia Senior Software Design Engineer IIS Core Server

• 01-06-2009, 3:51 PM

  In reply to

  Mike Trader Joined on 10-10-2008, 4:01 PM Posts 25

  Re: FastCGI terminating using POST method Reply Contact  Hi Anil, Thank you for you reply. This is an EXAMPLE of a use of chunked xfer. In this example, if i need to upload a 100MB file over a consumer connection, it could take hours, so breaking it up into smaller pieces makes sense from a TIMEOUT perspective, and also allows a broken connection to pick up with the last chunk that was sucessfully transfered.   But all of this is irellevant to the problem The point is FastCGI is not behaving as expected. My FastCGI process is being terminated depending on the size of the CONTENT_LENGTH. Can you explain this?