malloc in a DLL call => out of memory

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Thomas -

Windows normally provides 2GB of memory for applications (this can be increased to 3MB if needed). The heap used by VA Smalltalk (or any other application) is not limited other than by the total size of available memory.  

If you seem to be running out of memory, I have found the Sysinternals Process Explorer and VMMap tools (download from www.sysinternals.com or run directly from the web) to be of great help in understanding what is going on with memory -- particularly in determining whether all available memory is really being used or the error return is bogus (caused by something other than being out of momory -- the VM is famous for dong this).

Hi John

The problem happened (notice the past tense ;-)) in a 100% load test
environment. The server application got WebService (SOAP XML) calls
and ended up calling some DLL's for financial calculations.

The memory for the DLL structure is being freed during garbage
collection and scavenge.

Now - the system is bombarded with calls and the method
SstSockettransport>>findReadyConnection was trying to allocate memory
for the next socket (as no other were available). However, the
implementation with the "whileTrue:" loop at the top didn't allow the
other threads to free the memory.

So, what we did to resolve the issue was to add a

                [Processor finalizeCycle] whileTrue: [].
                Processor yield

in the loop just before the "This should never happen ;-)

The method looks now like this

findReadyConnection
        "--- Answer a connection which is ready-for-read.
                Answer nil to indicate a new connection request on our listening
socket.
                Answer an SstError on error.
        "

        | socket conn nread|

        [conn isNil] whileTrue: [

                self isShutDown ifTrue: [^SstError for: SstTransportShutDownError].

                [conn := knownReadyConnections isEmpty ifFalse:
[knownReadyConnections remove]] critical.
                conn isNil ifTrue: [
                        (socket := socketSieve next) == listeningSocket
                                ifTrue: [^nil].
                        socket isNil
                                ifTrue: ["-- notification read --"]
                                ifFalse: [
                                        socket isSstError
                                                ifTrue: [
                                                        socket errorCode = SstReceiveError
                                                                ifTrue: [self handleDeadSocketsError: socket in:
'findReadyConnection']
                                                                ifFalse: [^socket]]
                                                ifFalse: [
                                                        conn := self connectionManager
                                                                lookupConnectionForHandle: socket
                                                                ifAbsent: [^SstError for: SstInternalTransportError with:
(NlsCatSSTG indexedMsg: 112)]]]].
                [Processor finalizeCycle] whileTrue: [].
                Processor yield.
        ].    "$NLS$ This should never happen."

        (nread := conn handle ioctl: FIONREAD parameter: nil) isSciError
                ifTrue: [
                        ((Array with: ENOTSOCK with: ECONNRESET with: EBADF) includes:
nread errorCode)
                                ifTrue: [
                                        self logWarning: ('%1>>findReadyConnection ... discarding dead
socket (%2) for connection to peer @ %3.'
                                                bindWith: self class name
                                                with: conn handle platformHandle printString
                                                with: conn peer address printString)]
                                ifFalse: [


On Aug 8, 7:44 pm, John O'Keefe <[hidden email]> wrote:
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Thomas -

I've opened Case 48631: SstSocketTransport>>findReadyConnection can starve other Processes on your behalf for this problem. We will report back here, as well as directly to you, after we have analyzed the problem.  

John

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