Tuxedo Memory Leak Issue (Tuxedo 8.1 - Windows Server 2003)

Question

Hi
We are running tuxedo 8.1, 32 bit with patch level 258 in our windows server 2003 based production environment. We are currently facing an issue where the memory usage of machine slowly keeps on going higher and higher eventually resulting in “Memory Allocation Failure” to tuxedo servers. We then have to do a complete restart of tuxedo which stabilizes the system for other few days.
We have been analyzing the our source code in development/test environment using different tools like a customized Alzheimer tool and IBM purify but both tools reported no memory leaks. We then developed a test tuxedo server exposing a tuxedo service which simply allocates a memory to a response buffer and then returns the response buffer. I then configured tuxedo queue with same name “MEMTEST3” and configured a TMQForward server to call this “MEMTEST3” service every time a message is en-queued to the MEMTEST3 queue.
unsigned long _LIBENTRY ulTPAlloc(FBFR32 **ppc, long size)
unsigned long ulRes = MSG_SUCCESS_c;
ppc = (FBFR32 ) tpalloc("FML32", (char *) 0, size);
if (*ppc == (FBFR32 *) 0) {
vLogMessage(hGetLogHandle(), MSG_MEM_ALLOC_ERR_c, (char *) 0, (Event_t *) 0,
BM_NOSUPPRESS_c, size);
ulRes = MSG_MEM_ALLOC_ERR_c;
return (ulRes);
/*==============================================================================
Service MEMTEST2
==============================================================================*/
void MEMTEST3(TPSVCINFO *pRequest)
FBFR32 *pFmlResponse = NULL;
FBFR32 *pFml = NULL;
unsigned long ulRes = MSG_SUCCESS_c;
unsigned long ulActionCode = 0;
int iExitValue = 0;
long lTpurcode = 0;
FBFR32 *pFmlNULL = NULL;
userlog("Starting MEMTEST3 service.");
if (pRequest == NULL || pRequest->data == NULL)
vLogMessage(hGetLogHandle(), MSG_API_ARGS_ERR_c, NULL, NULL, BM_NOSUPPRESS_c);
ulRes = MSG_API_ARGS_ERR_c;
else
pFml = (FBFR32 *) pRequest->data;
userlog("MEMTEST3: GET THE MEM");
ulRes = ulTPAlloc(&pFmlResponse, 1024);
userlog("Ending MEMTEST3 service.");
tpreturn( iExitValue, lTpurcode, ( char * ) pFmlResponse , 0L, 0L );
While I was en-queuing the messages to the queue, I kept on monitoring the memory usage of the server hosting the service. What I observed was that I saw an initial hike in the usage of memory of the server followed by small jumps in memory increase. I kept on monitoring the server for a long time and the memory was never returned. What I suspect is that there is memory leak in tuxedo TMQforward process as it never released the memory allocated in the service.
Can anyone help how this situation can be avoided ?
Kind Regards,
Asim

Answer 1

Hi Todd,
Also as well as my previous question, I also found your reply to another user posting something similar at Re: Memory leaks in Tuxedo libraries
You mention that:
In general Tuxedo will free anything it allocates, although there are cases where memory is allocated and not freed because:
+1) it is one time or a fixed number of times allocations that will not continue to grow, and freeing up the memory just before exiting isn't of any benefit.+
+2) the memory is under Tuxedo's memory management functions where we manage our own look aside lists to provide better buffer allocation performance and again freeing these before process termination is of little benefit.+
Our code does only issue TPALLOC once and then a TPRETURN - could point (1) of your comment above also be something of concern to us, where we would observe a continuous growth of memory usage?
I know it may sound like a stupid question but do we need to run our code 20,000 times before memory gets freed?
Kind Regards,
Asim