Commit f507b377 authored by unknown's avatar unknown
Browse files

ndb - Handle shm-transporter wo/ busy-wait + also 

      handled mixed tcp/shm transporters
+ bug#7124


ndb/src/common/transporter/SHM_Transporter.cpp:
  Add remote/own pid for signaling availability of data on shm-segment
ndb/src/common/transporter/SHM_Transporter.hpp:
  Add remote/own pid for signaling availability of data on shm-segment
ndb/src/common/transporter/TransporterRegistry.cpp:
  Add remote/own pid for signaling availability of data on shm-segment
ndb/src/kernel/main.cpp:
  Set pid to use for shm-signaling
ndb/src/mgmsrv/ConfigInfo.cpp:
  bug#7124
ndb/src/ndbapi/TransporterFacade.cpp:
  Set pid to use for shm-signaling
parent f67fe154

ndb/src/common/transporter/SHM_Transporter.cpp

+39 −44
Original line number Diff line number Diff line
@@ -26,6 +26,8 @@ 
#include <InputStream.hpp>

#include <OutputStream.hpp>



extern int g_shm_pid;



SHM_Transporter::SHM_Transporter(TransporterRegistry &t_reg,

				 const char *lHostName,

				 const char *rHostName,
@@ -52,6 +54,7 @@ SHM_Transporter::SHM_Transporter(TransporterRegistry &t_reg, 
#ifdef DEBUG_TRANSPORTER

  printf("shm key (%d - %d) = %d\n", lNodeId, rNodeId, shmKey);

#endif

  m_signal_threshold = 4096;

}



SHM_Transporter::~SHM_Transporter(){
@@ -182,42 +185,6 @@ SHM_Transporter::setupBuffers(){ 
#endif

}



#if 0

SendStatus

SHM_Transporter::prepareSend(const SignalHeader * const signalHeader, 

			     Uint8 prio,

			     const Uint32 * const signalData, 

			     const LinearSegmentPtr ptr[3],

			     bool force){

  

  if(isConnected()){



    const Uint32 lenBytes = m_packer.getMessageLength(signalHeader, ptr);



    Uint32 * insertPtr = (Uint32 *)writer->getWritePtr(lenBytes);



    if(insertPtr != 0){

      

      m_packer.pack(insertPtr, prio, signalHeader, signalData, ptr);

      

      /**

       * Do funky membar stuff

       */

      

      writer->updateWritePtr(lenBytes);

      return SEND_OK;

      

    } else {

      //      NdbSleep_MilliSleep(3);

      //goto tryagain;

      return SEND_BUFFER_FULL;

    }

  }

  return SEND_DISCONNECTED;

}

#endif





bool

SHM_Transporter::connect_server_impl(NDB_SOCKET_TYPE sockfd)

{
@@ -247,10 +214,17 @@ SHM_Transporter::connect_server_impl(NDB_SOCKET_TYPE sockfd) 
  }



  // Send ok to client

  s_output.println("shm server 1 ok");

  s_output.println("shm server 1 ok: %d", g_shm_pid);

  

  // Wait for ok from client

  if (s_input.gets(buf, 256) == 0) {

  if (s_input.gets(buf, 256) == 0) 

  {

    NDB_CLOSE_SOCKET(sockfd);

    DBUG_RETURN(false);

  }



  if(sscanf(buf, "shm client 1 ok: %d", &m_remote_pid) != 1)

  {

    NDB_CLOSE_SOCKET(sockfd);

    DBUG_RETURN(false);

  }
@@ -289,6 +263,12 @@ SHM_Transporter::connect_client_impl(NDB_SOCKET_TYPE sockfd) 
    DBUG_RETURN(false);

  }



  if(sscanf(buf, "shm server 1 ok: %d", &m_remote_pid) != 1)

  {

    NDB_CLOSE_SOCKET(sockfd);

    DBUG_RETURN(false);

  }

  

  // Create

  if(!_shmSegCreated){

    if (!ndb_shm_get()) {
@@ -313,7 +293,7 @@ SHM_Transporter::connect_client_impl(NDB_SOCKET_TYPE sockfd) 
  }



  // Send ok to server

  s_output.println("shm client 1 ok");

  s_output.println("shm client 1 ok: %d", g_shm_pid);

  

  int r= connect_common(sockfd);
@@ -344,18 +324,33 @@ SHM_Transporter::connect_common(NDB_SOCKET_TYPE sockfd) 
    return false;

  }

  

  if(!setupBuffersDone) {

  if(!setupBuffersDone) 

  {

    setupBuffers();

    setupBuffersDone=true;

  }



  if(setupBuffersDone) {

  if(setupBuffersDone) 

  {

    NdbSleep_MilliSleep(m_timeOutMillis);

    if(*serverStatusFlag == 1 && *clientStatusFlag == 1)

    {

      m_last_signal = 0;

      return true;

    }

  }



  DBUG_PRINT("error", ("Failed to set up buffers to node %d",

              remoteNodeId));

  return false;

}



void

SHM_Transporter::doSend()

{

  if(m_last_signal)

  {

    m_last_signal = 0;

    kill(m_remote_pid, SIGUSR1);

  }

}

ndb/src/common/transporter/SHM_Transporter.hpp

+24 −9
Original line number Diff line number Diff line
@@ -53,12 +53,19 @@ public: 
   */

  bool initTransporter();

  

  Uint32 * getWritePtr(Uint32 lenBytes, Uint32 prio){

  Uint32 * getWritePtr(Uint32 lenBytes, Uint32 prio)

  {

    return (Uint32 *)writer->getWritePtr(lenBytes);

  }

  

  void updateWritePtr(Uint32 lenBytes, Uint32 prio){

  void updateWritePtr(Uint32 lenBytes, Uint32 prio)

  {

    writer->updateWritePtr(lenBytes);

    m_last_signal += lenBytes;

    if(m_last_signal >= m_signal_threshold)

    {

      doSend();

    }

  }

  

  void getReceivePtr(Uint32 ** ptr, Uint32 ** eod){
@@ -123,6 +130,14 @@ protected: 
   */

  void setupBuffers();



  /**

   * doSend (i.e signal receiver)

   */

  void doSend();

  int m_remote_pid;

  Uint32 m_last_signal;

  Uint32 m_signal_threshold;

  

private:

  bool _shmSegCreated;

  bool _attached;

ndb/src/common/transporter/TransporterRegistry.cpp

+213 −185
Original line number Diff line number Diff line
@@ -47,6 +47,8 @@ 
#include <InputStream.hpp>

#include <OutputStream.hpp>



int g_shm_pid = 0;



SocketServer::Session * TransporterService::newSession(NDB_SOCKET_TYPE sockfd)

{

  DBUG_ENTER("SocketServer::Session * TransporterService::newSession");
@@ -622,11 +624,28 @@ TransporterRegistry::pollReceive(Uint32 timeOutMillis){ 
  return retVal;

#endif

  

  if((nSHMTransporters+nSCITransporters) > 0)

  if((nSCITransporters) > 0)

  {

    timeOutMillis=0;

  }



#ifdef NDB_SHM_TRANSPORTER

  if(nSHMTransporters > 0)

  {

    Uint32 res = poll_SHM(0);

    if(res)

    {

      retVal |= res;

      timeOutMillis = 0;

    }

  }

#endif



#ifdef NDB_TCP_TRANSPORTER

  if(nTCPTransporters > 0)

  if(nTCPTransporters > 0 || retVal == 0)

  {

    retVal |= poll_TCP(timeOutMillis);

  }

  else

    tcpReadSelectReply = 0;

#endif
@@ -635,8 +654,11 @@ TransporterRegistry::pollReceive(Uint32 timeOutMillis){ 
    retVal |= poll_SCI(timeOutMillis);

#endif

#ifdef NDB_SHM_TRANSPORTER

  if(nSHMTransporters > 0)

    retVal |= poll_SHM(timeOutMillis);

  if(nSHMTransporters > 0 && retVal == 0)

  {

    int res = poll_SHM(0);

    retVal |= res;

  }

#endif

  return retVal;

}
@@ -644,8 +666,8 @@ TransporterRegistry::pollReceive(Uint32 timeOutMillis){ 


#ifdef NDB_SCI_TRANSPORTER

Uint32

TransporterRegistry::poll_SCI(Uint32 timeOutMillis){

 

TransporterRegistry::poll_SCI(Uint32 timeOutMillis)

{

  for (int i=0; i<nSCITransporters; i++) {

    SCI_Transporter * t = theSCITransporters[i];

    if (t->isConnected()) {
@@ -659,73 +681,29 @@ TransporterRegistry::poll_SCI(Uint32 timeOutMillis){ 




#ifdef NDB_SHM_TRANSPORTER

static int g_shm_counter = 0;

Uint32

TransporterRegistry::poll_SHM(Uint32 timeOutMillis)

{  

  for(int j=0; j < 20; j++)

  for (int i=0; i<nSHMTransporters; i++) {

    SHM_Transporter * t = theSHMTransporters[i];

    if (t->isConnected()) {

      if(t->hasDataToRead()) {

	return 1;

      }

    }

  }

  /**

   * @note: granularity of linux/i386 timer is not good enough.

   * Can't sleep if using SHM as it is now.

   */

  /*

    if(timeOutMillis > 0)

    NdbSleep_MilliSleep(timeOutMillis);

    else 

    NdbSleep_MilliSleep(1);

  */

  return 0;

#if 0

  NDB_TICKS startTime =   NdbTick_CurrentMillisecond();

  for(int i=0; i<100; i++) {

  for(int j=0; j < 100; j++)

  {

    for (int i=0; i<nSHMTransporters; i++) {

      SHM_Transporter * t = theSHMTransporters[i];

      if (t->isConnected()) {

	if(t->hasDataToRead()) {

	  return 1;

	}

	else

	  continue;

      }

      else

	continue;

    }



    if(NdbTick_CurrentMillisecond() > (startTime +timeOutMillis))

      return 0;      

  }

  NdbSleep_MilliSleep(5);

  return 0;

  

#endif

#if 0



  for(int j=0; j < 100; j++) {

    for (int i=0; i<nSHMTransporters; i++) {

      SHM_Transporter * t = theSHMTransporters[i];

      if (t->isConnected()) {

	if(t->hasDataToRead())

	  return 1;

      }

    }

}

  return 0;

#endif

}





#endif



#ifdef NDB_OSE_TRANSPORTER

Uint32

TransporterRegistry::poll_OSE(Uint32 timeOutMillis){

TransporterRegistry::poll_OSE(Uint32 timeOutMillis)

{

  if(theOSEReceiver != NULL){

    return theOSEReceiver->doReceive(timeOutMillis);

  }
@@ -736,16 +714,16 @@ TransporterRegistry::poll_OSE(Uint32 timeOutMillis){ 


#ifdef NDB_TCP_TRANSPORTER

Uint32 

TransporterRegistry::poll_TCP(Uint32 timeOutMillis){

  

  if (nTCPTransporters == 0){

TransporterRegistry::poll_TCP(Uint32 timeOutMillis)

{

  if (false && nTCPTransporters == 0)

  {

    tcpReadSelectReply = 0;

    return 0;

  }

  

  struct timeval timeout;

#ifdef NDB_OSE



  // Return directly if there are no TCP transporters configured

  

  if(timeOutMillis <= 1){
@@ -760,7 +738,7 @@ TransporterRegistry::poll_TCP(Uint32 timeOutMillis){ 
  timeout.tv_usec = (timeOutMillis % 1000) * 1000;

#endif



  NDB_SOCKET_TYPE maxSocketValue = 0;

  NDB_SOCKET_TYPE maxSocketValue = -1;

  

  // Needed for TCP/IP connections

  // The read- and writeset are used by select
@@ -788,6 +766,9 @@ TransporterRegistry::poll_TCP(Uint32 timeOutMillis){ 
  maxSocketValue++; 

  

  tcpReadSelectReply = select(maxSocketValue, &tcpReadset, 0, 0, &timeout);  

  if(false && tcpReadSelectReply == -1 && errno == EINTR)

    ndbout_c("woke-up by signal");



#ifdef NDB_WIN32

  if(tcpReadSelectReply == SOCKET_ERROR)

  {
@@ -801,10 +782,13 @@ TransporterRegistry::poll_TCP(Uint32 timeOutMillis){ 




void

TransporterRegistry::performReceive(){

TransporterRegistry::performReceive()

{

#ifdef NDB_OSE_TRANSPORTER

  if(theOSEReceiver != 0){

    while(theOSEReceiver->hasData()){

  if(theOSEReceiver != 0)

  {

    while(theOSEReceiver->hasData())

    {

      NodeId remoteNodeId;

      Uint32 * readPtr;

      Uint32 sz = theOSEReceiver->getReceiveData(&remoteNodeId, &readPtr);
@@ -827,16 +811,20 @@ TransporterRegistry::performReceive(){ 
#endif



#ifdef NDB_TCP_TRANSPORTER

  if(tcpReadSelectReply > 0){

    for (int i=0; i<nTCPTransporters; i++) {

  if(tcpReadSelectReply > 0)

  {

    for (int i=0; i<nTCPTransporters; i++) 

    {

      checkJobBuffer();

      TCP_Transporter *t = theTCPTransporters[i];

      const NodeId nodeId = t->getRemoteNodeId();

      const NDB_SOCKET_TYPE socket    = t->getSocket();

      if(is_connected(nodeId)){

	if(t->isConnected() && FD_ISSET(socket, &tcpReadset)) {

	if(t->isConnected() && FD_ISSET(socket, &tcpReadset)) 

	{

	  const int receiveSize = t->doReceive();

	  if(receiveSize > 0){

	  if(receiveSize > 0)

	  {

	    Uint32 * ptr;

	    Uint32 sz = t->getReceiveData(&ptr);

	    Uint32 szUsed = unpack(ptr, sz, nodeId, ioStates[nodeId]);
@@ -848,16 +836,18 @@ TransporterRegistry::performReceive(){ 
  }

#endif

  



#ifdef NDB_SCI_TRANSPORTER

  //performReceive

  //do prepareReceive on the SCI transporters  (prepareReceive(t,,,,))

    for (int i=0; i<nSCITransporters; i++) {

  for (int i=0; i<nSCITransporters; i++) 

  {

    checkJobBuffer();

    SCI_Transporter  *t = theSCITransporters[i];

    const NodeId nodeId = t->getRemoteNodeId();

      if(is_connected(nodeId)){

	if(t->isConnected() && t->checkConnected()){

    if(is_connected(nodeId))

    {

      if(t->isConnected() && t->checkConnected())

      {

	Uint32 * readPtr, * eodPtr;

	t->getReceivePtr(&readPtr, &eodPtr);

	Uint32 *newPtr = unpack(readPtr, eodPtr, nodeId, ioStates[nodeId]);
@@ -867,12 +857,14 @@ TransporterRegistry::performReceive(){ 
  }

#endif

#ifdef NDB_SHM_TRANSPORTER

    for (int i=0; i<nSHMTransporters; i++) {

  for (int i=0; i<nSHMTransporters; i++) 

  {

    checkJobBuffer();

    SHM_Transporter *t = theSHMTransporters[i];

    const NodeId nodeId = t->getRemoteNodeId();

    if(is_connected(nodeId)){

	if(t->isConnected() && t->checkConnected()){

      if(t->isConnected() && t->checkConnected())

      {

	Uint32 * readPtr, * eodPtr;

	t->getReceivePtr(&readPtr, &eodPtr);

	Uint32 *newPtr = unpack(readPtr, eodPtr, nodeId, ioStates[nodeId]);
@@ -885,15 +877,17 @@ TransporterRegistry::performReceive(){ 


static int x = 0;

void

TransporterRegistry::performSend(){

TransporterRegistry::performSend()

{

  int i; 

  sendCounter = 1;

  

#ifdef NDB_OSE_TRANSPORTER

    for (int i = 0; i < nOSETransporters; i++){

  for (int i = 0; i < nOSETransporters; i++)

  {

    OSE_Transporter *t = theOSETransporters[i]; 

        if((is_connected(t->getRemoteNodeId()) &&

            (t->isConnected())) {

    if(is_connected(t->getRemoteNodeId()) &&& (t->isConnected()))

    {

      t->doSend();

    }//if

  }//for
@@ -932,7 +926,8 @@ TransporterRegistry::performSend(){ 
    struct timeval timeout = { 0, 1025 };

    Uint32 tmp = select(maxSocketValue, 0, &writeset, 0, &timeout);

    

        if (tmp == 0) {

    if (tmp == 0) 

    {

      return;

    }//if

    for (i = 0; i < nTCPTransporters; i++) {
@@ -948,24 +943,24 @@ TransporterRegistry::performSend(){ 
    }

#endif

#ifdef NDB_TCP_TRANSPORTER

    for (i = x; i < nTCPTransporters; i++) {

  for (i = x; i < nTCPTransporters; i++) 

  {

    TCP_Transporter *t = theTCPTransporters[i];

        if (t &&

            (t->hasDataToSend()) &&

            (t->isConnected()) &&

            (is_connected(t->getRemoteNodeId()))) {

    if (t && t->hasDataToSend() && t->isConnected() &&

	is_connected(t->getRemoteNodeId())) 

    {

      t->doSend();

        }//if

    }//for

    for (i = 0; i < x && i < nTCPTransporters; i++) {

    }

  }

  for (i = 0; i < x && i < nTCPTransporters; i++) 

  {

    TCP_Transporter *t = theTCPTransporters[i];

        if (t &&

            (t->hasDataToSend()) &&

            (t->isConnected()) &&

            (is_connected(t->getRemoteNodeId()))) {

    if (t && t->hasDataToSend() && t->isConnected() &&

	is_connected(t->getRemoteNodeId())) 

    {

      t->doSend();

        }//if

    }//for

    }

  }

  x++;

  if (x == nTCPTransporters) x = 0;

#endif
@@ -977,12 +972,28 @@ TransporterRegistry::performSend(){ 
    SCI_Transporter  *t = theSCITransporters[i];

    const NodeId nodeId = t->getRemoteNodeId();

    

      if(is_connected(nodeId)){

    if(is_connected(nodeId))

    {

      if(t->isConnected() && t->hasDataToSend()) {

	t->doSend();

      } //if

    } //if

    }  //if  

  }

#endif

  

#ifdef NDB_SHM_TRANSPORTER

  for (i=0; i<nSHMTransporters; i++) 

  {

    SHM_Transporter  *t = theSHMTransporters[i];

    const NodeId nodeId = t->getRemoteNodeId();

    if(is_connected(nodeId))

    {

      if(t->isConnected())

      {

	t->doSend();

      }

    }

  }

#endif

}
@@ -1169,7 +1180,8 @@ TransporterRegistry::stop_clients() 
}



void

TransporterRegistry::add_transporter_interface(const char *interface, unsigned short port)

TransporterRegistry::add_transporter_interface(const char *interface, 

					       unsigned short port)

{

  DBUG_ENTER("TransporterRegistry::add_transporter_interface");

  DBUG_PRINT("enter",("interface=%s, port= %d", interface, port));
@@ -1232,6 +1244,15 @@ TransporterRegistry::start_service(SocketServer& socket_server) 
  return true;

}



#ifdef NDB_SHM_TRANSPORTER

static

RETSIGTYPE 

shm_sig_handler(int signo)

{

  g_shm_counter++;

}

#endif



void

TransporterRegistry::startReceiving()

{
@@ -1250,6 +1271,13 @@ TransporterRegistry::startReceiving() 
  for(int i = 0; i<nTCPTransporters; i++)

    theTCPTransporters[i]->theReceiverPid = theReceiverPid;

#endif



#ifdef NDB_SHM_TRANSPORTER

  if(nSHMTransporters)

  {

    signal(SIGUSR1, shm_sig_handler);

  }

#endif

}



void

ndb/src/kernel/main.cpp

+3 −0
Original line number Diff line number Diff line
@@ -49,6 +49,8 @@ void catchsigs(bool ignore); // for process signal handling 
extern "C" void handler_shutdown(int signum);  // for process signal handling

extern "C" void handler_error(int signum);  // for process signal handling



extern int g_shm_pid;



// Shows system information

void systemInfo(const Configuration & conf,

		const LogLevel & ll);
@@ -145,6 +147,7 @@ int main(int argc, char** argv) 
  }



  g_eventLogger.info("Angel pid: %d ndb pid: %d", getppid(), getpid());

  g_shm_pid = getpid();

  theConfig->setupConfiguration();

  systemInfo(* theConfig, * theConfig->m_logLevel);

ndb/src/mgmsrv/ConfigInfo.cpp

+53 −10
Original line number Diff line number Diff line
@@ -82,7 +82,7 @@ static bool transformConnection(InitConfigFileParser::Context & ctx, const char 
static bool applyDefaultValues(InitConfigFileParser::Context & ctx, const char *);

static bool checkMandatory(InitConfigFileParser::Context & ctx, const char *);

static bool fixPortNumber(InitConfigFileParser::Context & ctx, const char *);

static bool fixShmkey(InitConfigFileParser::Context & ctx, const char *);

static bool fixShmKey(InitConfigFileParser::Context & ctx, const char *);

static bool checkDbConstraints(InitConfigFileParser::Context & ctx, const char *);

static bool checkConnectionConstraints(InitConfigFileParser::Context &, const char *);

static bool checkTCPConstraints(InitConfigFileParser::Context &, const char *);
@@ -131,13 +131,15 @@ ConfigInfo::m_SectionRules[] = { 
  { "TCP",  fixHostname, "HostName2" },

  { "SCI",  fixHostname, "HostName1" },

  { "SCI",  fixHostname, "HostName2" },

  { "SHM",  fixHostname, "HostName1" },

  { "SHM",  fixHostname, "HostName2" },

  { "OSE",  fixHostname, "HostName1" },

  { "OSE",  fixHostname, "HostName2" },



  { "TCP",  fixPortNumber, 0 }, // has to come after fixHostName

  { "SHM",  fixPortNumber, 0 }, // has to come after fixHostName

  { "SCI",  fixPortNumber, 0 }, // has to come after fixHostName

  //{ "SHM",  fixShmKey, 0 },

  { "SHM",  fixShmKey, 0 },



  /**

   * fixExtConnection must be after fixNodeId
@@ -168,6 +170,8 @@ ConfigInfo::m_SectionRules[] = { 
  { "TCP",  checkTCPConstraints, "HostName2" },

  { "SCI",  checkTCPConstraints, "HostName1" },

  { "SCI",  checkTCPConstraints, "HostName2" },

  { "SHM",  checkTCPConstraints, "HostName1" },

  { "SHM",  checkTCPConstraints, "HostName2" },

  

  { "*",    checkMandatory, 0 },
@@ -1687,14 +1691,25 @@ const ConfigInfo::ParamInfo ConfigInfo::m_ParamInfo[] = { 
    0, 0 },



  {

    CFG_CONNECTION_NODE_1,

    "NodeId1",

    CFG_CONNECTION_HOSTNAME_1,

    "HostName1",

    "SHM",

    "Id of node ("DB_TOKEN_PRINT", "API_TOKEN_PRINT" or "MGM_TOKEN_PRINT") on one side of the connection",

    ConfigInfo::USED,

    "Name/IP of computer on one side of the connection",

    ConfigInfo::INTERNAL,

    false,

    ConfigInfo::STRING,

    MANDATORY,

    UNDEFINED,

    0, 0 },



  {

    CFG_CONNECTION_HOSTNAME_2,

    "HostName2",

    "SHM",

    "Name/IP of computer on one side of the connection",

    ConfigInfo::INTERNAL,

    false,

    ConfigInfo::STRING,

    UNDEFINED,

    0, 0 },



  {
@@ -1709,6 +1724,17 @@ const ConfigInfo::ParamInfo ConfigInfo::m_ParamInfo[] = { 
    "0", 

    STR_VALUE(MAX_INT_RNIL) },



  {

    CFG_CONNECTION_NODE_1,

    "NodeId1",

    "SHM",

    "Id of node ("DB_TOKEN_PRINT", "API_TOKEN_PRINT" or "MGM_TOKEN_PRINT") on one side of the connection",

    ConfigInfo::USED,

    false,

    ConfigInfo::STRING,

    MANDATORY,

    0, 0 },

  

  {

    CFG_CONNECTION_NODE_2,

    "NodeId2",
@@ -3025,15 +3051,32 @@ fixPortNumber(InitConfigFileParser::Context & ctx, const char * data){ 
	   << "per connection, please remove from config. "

	   << "Will be changed to " << port << endl;

    ctx.m_currentSection->put("PortNumber", port, true);

  } else

  } 

  else

  {

    ctx.m_currentSection->put("PortNumber", port);



  }

  DBUG_PRINT("info", ("connection %d-%d port %d host %s",

		      id1, id2, port, hostname.c_str()));



  DBUG_RETURN(true);

}



static 

bool 

fixShmKey(InitConfigFileParser::Context & ctx, const char *)

{

  Uint32 id1= 0, id2= 0, key= 0;

  require(ctx.m_currentSection->get("NodeId1", &id1));

  require(ctx.m_currentSection->get("NodeId2", &id2));

  if(ctx.m_currentSection->get("ShmKey", &key))

    return true;



  key= (id1 > id2 ? id1 << 16 | id2 : id2 << 16 | id1);

  ctx.m_currentSection->put("ShmKey", key);

  return true;

}



/**

 * DB Node rule: Check various constraints

 */