Sorry for replying to myself, but I thought some other people might benefit from seeing a few references.
It seems what I am interested in is the following question: Does Mono support overlapped IO on the asynchronous socket calls. Winsock does support this. It seems the .Net framework is supposed to support this. When I put a server under heavily load, this fails on mono 0.31 on debian unstable. Any Mono guru's out there care to comment on Overlapped IO on Sockets in mono? I have found some background links discussing various issues with overlapped IO and unix: Wine has had to deal with this: http://www.winehq.org/hypermail/wine-devel/2001/11/0020.html http://www.kerneltraffic.org/wine/wn20020726_130.html#3 Here is a discussion about IO models in winsock programming which sings the praises of overlapped IO: http://tangentsoft.net/wskfaq/articles/io-strategies.html I am having a hard time writing a test case only using sockets which can expose (what a believe to be) the bug. In my code, I have ~50 sockets which are created with a lot of data being copied between the sockets. At that point, I start to see sockets which just stop working. For instance, BeginSend methods stop calling the callback function, and the socket basically gets stuck (some internal deadlock maybe?) I looked at the code for the System.Net.Sockets.Socket class. It seems to implement the BeginSend and BeginReceive methods just using a Worker without any attempt at any kind of thread safety (which I can imagine would cause problems if you call interleaved BeginSend and BeginRead). Best, Oscar On Tue, Apr 27, 2004 at 05:33:04PM -0700, P Oscar Boykin wrote: > Hello All, > > I have some code that does asynchronous Socket.BeginSend and > Socket.BeginReceive calls. > > My question is the following: > > 1) The documentation (in monodoc) says that no instance members of > Socket are guaranteed to be thread safe. > > 2) Given the above, is it safe to have a BeginSend call active while a > BeginReceive call is also active? Given that the "under the hood" it > appears that these methods are implemented with threads. > > So, to make it clear, if I have code like: > > -------------- > BeginSend() > BeginReceive() > > [ other stuff here ] > > EndReceive() > EndSend() > ------------- > > is this safe? To me, it would seem like it would not be safe if none of > the members are guaranteed to be thread safe, but on the other hand, I > have a C# networking book that has examples such as this. > > The reason I ask is that I have some code that (on mono 0.31) appears > that *SOMETIMES* the BeginSend never calls the callback function to > indicate that it finished (and the other side never gets the data). > This is happening while a BeginReceive() is active. > > When I see bugs that happen only sometimes, it usually makes me worry > about thread safety. It would be nice if the Begin* methods were > designed such that there could be more than one of them active at a time > (particularly, it would be nice to have a send going on while a receive > was also active). > > Am I expecting too much here? > > Thanks, > Oscar > -- > [EMAIL PROTECTED] http://pobox.com/~boykin jabber: [EMAIL PROTECTED] > fingerprint=D250 4AD9 4544 B7D2 A17C 911D D608 D387 6718 D75F > Hague Convention is Bad News: http://www.gnu.org/philosophy/hague.html -- [EMAIL PROTECTED] http://pobox.com/~boykin jabber: [EMAIL PROTECTED] fingerprint=D250 4AD9 4544 B7D2 A17C 911D D608 D387 6718 D75F Read about net freedom: http://www.politechbot.com/
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