| Ian Wienand | 2bbc9bb | 2019-02-11 12:25:38 +1100 | [diff] [blame] | 1 | ===================== |
| 2 | System-wide debugging |
| 3 | ===================== |
| 4 | |
| 5 | A lot can go wrong during a devstack run, and there are a few inbuilt |
| 6 | tools to help you. |
| 7 | |
| 8 | dstat |
| 9 | ----- |
| 10 | |
| 11 | Enable the ``dstat`` service to produce performance logs during the |
| 12 | devstack run. These will be logged to the journal and also as a CSV |
| 13 | file. |
| 14 | |
| 15 | memory_tracker |
| 16 | -------------- |
| 17 | |
| 18 | The ``memory_tracker`` service periodically monitors RAM usage and |
| 19 | provides consumption output when available memory is seen to be |
| 20 | falling (i.e. processes are consuming memory). It also provides |
| 21 | output showing locked (unswappable) memory. |
| 22 | |
| 23 | tcpdump |
| 24 | ------- |
| 25 | |
| 26 | Enable the ``tcpdump`` service to run a background tcpdump. You must |
| 27 | set the ``TCPDUMP_ARGS`` variable to something suitable (there is no |
| 28 | default). For example, to trace iSCSI communication during a job in |
| 29 | the OpenStack gate and copy the result into the log output, you might |
| 30 | use: |
| 31 | |
| 32 | .. code-block:: yaml |
| 33 | |
| 34 | job: |
| 35 | name: devstack-job |
| 36 | parent: devstack |
| 37 | vars: |
| 38 | devstack_services: |
| 39 | tcpdump: true |
| 40 | devstack_localrc: |
| 41 | TCPDUMP_ARGS: "-i any tcp port 3260" |
| 42 | zuul_copy_output: |
| 43 | '{{ devstack_log_dir }}/tcpdump.pcap': logs |
| 44 | |
| 45 | |
| 46 | |