focal (3) mongoc_basic_troubleshooting.3.gz

Provided by: libmongoc-doc_1.16.1-1build2_all bug

NAME
       mongoc_basic_troubleshooting - Basic Troubleshooting


TROUBLESHOOTING CHECKLIST
       The following is a short list of things to check when you have a problem.

       • Did you call mongoc_init() in main()? If not, you will likely see a segfault.

       • Have you leaked any clients or cursors as can be found with mongoc-stat <PID>?

       • Have packets been delivered to the server? See egress bytes from mongoc-stat <PID>.

       • Does  valgrind  show  any leaks? Ensure you call mongoc_cleanup() at the end of your process to cleanup
         lingering allocations from the MongoDB C driver.

       • If compiling your own copy of MongoDB C Driver, consider using the cmake option -DENABLE_TRACING=ON  to
         enable function tracing and hex dumps of network packets to STDERR and STDOUT.


PERFORMANCE COUNTERS
       The  MongoDB C driver comes with an optional unique feature to help developers and sysadmins troubleshoot
       problems in production.  Performance counters are available  for  each  process  using  the  driver.   If
       available,  the  counters can be accessed outside of the application process via a shared memory segment.
       This means that you can graph statistics about your application process easily from tools like  Munin  or
       Nagios.  Your author often uses watch --interval=0.5 -d mongoc-stat $PID to monitor an application.

       Performance  counters  are  only  available  on  Linux  platforms  supporting shared memory segments.  On
       supported platforms they are enabled by default.  Applications can  be  built  without  the  counters  by
       specifying  the cmake option -DENABLE_SHM_COUNTERS=OFF. Additionally, if performance counters are already
       compiled, they can be disabled at runtime by specifying the environment variable MONGOC_DISABLE_SHM.

       Performance counters keep track of the following:

       • Active and Disposed Cursors

       • Active and Disposed Clients, Client Pools, and Socket Streams.

       • Number of operations sent and received, by type.

       • Bytes transferred and received.

       • Authentication successes and failures.

       • Number of wire protocol errors.

       To access counters for a given process,  simply  provide  the  process  id  to  the  mongoc-stat  program
       installed with the MongoDB C Driver.

          $ mongoc-stat 22203
             Operations : Egress Total        : The number of sent operations.                    : 13247
             Operations : Ingress Total       : The number of received operations.                : 13246
             Operations : Egress Queries      : The number of sent Query operations.              : 13247
             Operations : Ingress Queries     : The number of received Query operations.          : 0
             Operations : Egress GetMore      : The number of sent GetMore operations.            : 0
             Operations : Ingress GetMore     : The number of received GetMore operations.        : 0
             Operations : Egress Insert       : The number of sent Insert operations.             : 0
             Operations : Ingress Insert      : The number of received Insert operations.         : 0
             Operations : Egress Delete       : The number of sent Delete operations.             : 0
             Operations : Ingress Delete      : The number of received Delete operations.         : 0
             Operations : Egress Update       : The number of sent Update operations.             : 0
             Operations : Ingress Update      : The number of received Update operations.         : 0
             Operations : Egress KillCursors  : The number of sent KillCursors operations.        : 0
             Operations : Ingress KillCursors : The number of received KillCursors operations.    : 0
             Operations : Egress Msg          : The number of sent Msg operations.                : 0
             Operations : Ingress Msg         : The number of received Msg operations.            : 0
             Operations : Egress Reply        : The number of sent Reply operations.              : 0
             Operations : Ingress Reply       : The number of received Reply operations.          : 13246
                Cursors : Active              : The number of active cursors.                     : 1
                Cursors : Disposed            : The number of disposed cursors.                   : 13246
                Clients : Active              : The number of active clients.                     : 1
                Clients : Disposed            : The number of disposed clients.                   : 0
                Streams : Active              : The number of active streams.                     : 1
                Streams : Disposed            : The number of disposed streams.                   : 0
                Streams : Egress Bytes        : The number of bytes sent.                         : 794931
                Streams : Ingress Bytes       : The number of bytes received.                     : 589694
                Streams : N Socket Timeouts   : The number of socket timeouts.                    : 0
           Client Pools : Active              : The number of active client pools.                : 1
           Client Pools : Disposed            : The number of disposed client pools.              : 0
               Protocol : Ingress Errors      : The number of protocol errors on ingress.         : 0
                   Auth : Failures            : The number of failed authentication requests.     : 0
                   Auth : Success             : The number of successful authentication requests. : 0


SUBMITTING A BUG REPORT
       Think  you've  found  a bug? Want to see a new feature in the MongoDB C driver? Please open a case in our
       issue management tool, JIRA:

       • Create an account and login.

       • Navigate to the CDRIVER project.

       • Click Create Issue - Please provide as much information as possible about the issue  type  and  how  to
         reproduce it.

       Bug  reports  in  JIRA  for  all  driver  projects (i.e. CDRIVER, CSHARP, JAVA) and the Core Server (i.e.
       SERVER) project are public.


AUTHOR
       MongoDB, Inc


       2017-present, MongoDB, Inc