| ===================== |
| System-wide debugging |
| ===================== |
| |
| A lot can go wrong during a devstack run, and there are a few inbuilt |
| tools to help you. |
| |
| dstat |
| ----- |
| |
| Enable the ``dstat`` service to produce performance logs during the |
| devstack run. These will be logged to the journal and also as a CSV |
| file. |
| |
| memory_tracker |
| -------------- |
| |
| The ``memory_tracker`` service periodically monitors RAM usage and |
| provides consumption output when available memory is seen to be |
| falling (i.e. processes are consuming memory). It also provides |
| output showing locked (unswappable) memory. |
| |
| tcpdump |
| ------- |
| |
| Enable the ``tcpdump`` service to run a background tcpdump. You must |
| set the ``TCPDUMP_ARGS`` variable to something suitable (there is no |
| default). For example, to trace iSCSI communication during a job in |
| the OpenStack gate and copy the result into the log output, you might |
| use: |
| |
| .. code-block:: yaml |
| |
| job: |
| name: devstack-job |
| parent: devstack |
| vars: |
| devstack_services: |
| tcpdump: true |
| devstack_localrc: |
| TCPDUMP_ARGS: "-i any tcp port 3260" |
| zuul_copy_output: |
| '{{ devstack_log_dir }}/tcpdump.pcap': logs |
| |
| |
| |