To add a new event edit the following 3 files in totally 5 places:

example shows EventBufferUsage added.

Public interface:

*** ndb/include/mgmapi/ndb_logevent.h

    /** NDB_MGM_EVENT_CATEGORY_INFO */
    NDB_LE_EventBufferUsage = 58
...


      /** Log event specific data for for corresponding NDB_LE_ log event */
      struct {
	unsigned usage;
	unsigned avail;
      } EventBufferUsage;

*** ndb/src/mgmapi/ndb_logevent.cpp

  ROW( EventBufferUsage, "usage", 1, usage),
  ROW( EventBufferUsage, "avail", 2, avail),



Internal impl:

*** ndb/src/common/debugger/EventLogger.cpp

void getTextEventBufferUsage(QQQQ) {
  BaseString::snprintf(m_text, m_text_len,
		       "Event buffer usage: %d(%d\%)",
		       theData[1],
		       theData[2] ? (theData[1]*100)/theData[2] : 0);
}

...

  ROW(EventBufferUsage,        LogLevel::llInfo,   7, Logger::LL_INFO ),

*** sending event from ndbd kernel

      Uint32 *data= signal->getDataPtrSend();
      data[0]= NDB_LE_EventBufferUsage;
      data[1]= 0;
      data[2]= 0;
      sendSignal(CMVMI_REF, GSN_EVENT_REP, signal, 3, JBB);

*** sending event from ndbapi (internal)

	Uint32 data[3];
	data[0]= NDB_LE_EventBufferUsage;
	data[1]= 0;
	data[2]= 0;
	m_ndb->theImpl->send_event_report(data,3);