[omniORB] COMM_FAILURE for "long" sequences

[Mårten Björkman]

Steve,

Thank you for you remark. Unfortunately, it's not due to improperly set 
giopMaxMsgSize, which I
believe is set to about 2M by default. Then I would have got an 
exception earlier and never reach
socket sent(). It seems that the limit is about 128K. I tested a minimal 
client-server thingie on another
(single processor) Linux machine running kernel version 2.4.20 and 
unfortunately got the same error.
If this were a Linux error, many others would have seen the same thing, 
I suppose. What makes an
omniORB based application different are the multiple threads. Somehow 
the ORB thread can not
read data stored by the server thread, if the sequence to be sent is 
longer than 128K.

See you in space,

Mårten

Steve Rowe wrote:

> I'm not sure about this, but have you adjusted your setting for 
> giopMaxMsgSize?  I believe you will get a Marshalling exception if 
> this isn't big enough for the GIOP message.
>
> Hope that helps
>
> - Steve Rowe
>
> At 08:59 AM 3/21/2005, celle at nada.kth.se wrote:
>
>> Hi all,
>>
>> I have been using omniORB for a number of years now, but never come
>> across a problem like this. For some reason I get COMM_FAILURE if the
>> size of a sequence<octet> is too large. So far I have been transfering
>> images of sizes 320x240 using a function GetImage (see the bit of code
>> below). However, when I changed the size to 640x480 is suddenly get
>> an exception.
>>
>> The server trace looks something like this:
>>
>> omniORB: Server accepted connection from giop:tcp:192.168.x.x:35693
>> omniORB: giopWorker task execute.
>> omniORB: Accepted connection from giop:tcp:192.168.x.x:35693
>> because of this rule: "* unix,ssl,tcp"
>> omniORB: inputMessage: from giop:tcp:192.168.x.x:35693 98 bytes
>> omniORB:  recieve codeset service context and set TCS to
>> (ISO-8859-1,UTF-16)
>> omniORB: sendChunk: to giop:tcp:192.168.x.x:35693 24 bytes
>> omniORB: inputMessage: from giop:tcp:192.168.x.x:35693 67 bytes
>> omniORB: sendChunk: to giop:tcp:192.168.x.x:35693 28 bytes
>> omniORB: sendCopyChunk: to giop:tcp:192.168.x.x:35693 307196 bytes
>> omniORB: throw giopStream::CommFailure from
>> giopStream.cc:1154(0,YES,COMM_FAILURE_MarshalResults)
>>
>> And the client one as follows:
>>
>> omniORB: Client attempt to connect to giop:tcp:192.168.x.x:35652
>> omniORB: Client opened connection to giop:tcp:192.168.x.x:35652
>> omniORB: sendChunk: to giop:tcp:192.168.x.x:35652 98 bytes
>> omniORB: inputMessage: from giop:tcp:192.168.x.x:35652 24 bytes
>> omniORB: sendChunk: to giop:tcp:192.168.x.x:35652 67 bytes
>> omniORB: inputMessage: from giop:tcp:192.168.x.x:35652 28 bytes
>> omniORB: throw giopStream::CommFailure from
>> giopStream.cc:876(0,MAYBE,COMM_FAILURE_WaitingForReply)
>>
>> The error occurs in function Send() in tcpConnection.cc. The UNIX
>> socket function send() returns EFAULT, which should mean that the
>> memory buffer (where data to be sent is stored) can't be accessed.
>> If I allocate a buffer (simply using new) the address space will
>> vary depending on the size of the buffer. Obviously, large buffers
>> will be allocated at address spaces where it can't be used by the
>> ORB. To me it seems like a Linux problem rather than a omniORB
>> problem, but if you have any comments I would be happy to hear.
>>
>> By the way, I use Linux with kernel version 2.4.18smp.
>>
>> Have a nice day,
>>
>> Mårten Björkman
>>
>>
>> ///////////// Simplified IDL file
>>
>> interface ImageTrans {
>>   typedef sequence<octet> SeqImage;
>>
>>   void GetImage(in short cam, in boolean jpeg, out SeqImage img,
>>     out short width, out short height, out long size);
>> };
>>
>>
>>
>> ////////// Server side function
>>
>> void ImageTransfer::GetImage(short cam, bool jpeg,
>>   ImageTrans::SeqImage_out seqimg, short &width, short &height,
>>   long int &totsize)
>> {
>>     mutex.lock();
>>     width = 320;
>>     height = 240;
>>     Image<unsigned char> limg(width, height); // Some image class
>>     // Some fiddling with the image
>>     totsize = width * height;
>>     seqimg = new ImageTrans::SeqImage(totsize, totsize,
>>        (CORBA::Octet*)limg.GetData(), false);
>>     mutex.unlock();
>> }
>>
>> /////////// Client side call
>>
>>     ImageTrans::SeqImage_var img;
>>     trans->GetImage(0, false, img, wid, hei, siz);
>>     Image<unsigned char> limg(wid, hei);
>>     unsigned char *lptr = limg.GetData();
>>     for (int i=0;i<wid*hei;i++)
>>        lptr[i] = img[i];
>>
>> /////////////////////////
>>
>>
>>
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>
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