On a Tuesday in 2022, Peter Krempa wrote:
The original patches adding the functionality neglected to add any form
of documentation for the stats fields returned for this group.
The stats are directly converted from qemu's 'query-stats(-schema)' QMP
command without any further interpretation. The 'query-stats-schema' has
the following disclaimer:
Note: runtime-collected statistics and their names fall outside QEMU's usual
deprecation policies. QEMU will try to keep the set of available data
stable, together with their names, but will not guarantee stability
at all costs; the same is true of providers that source statistics
externally, e.g. from Linux. For example, if the same value is being
tracked with different names on different architectures or by different
providers, one of them might be renamed. A statistic might go away if
an algorithm is changed or some code is removed; changing a default
might cause previously useful statistics to always report 0. Such
changes, however, are expected to be rare.
Since libvirt is not doing any form of conversion of the stats we can't
meaningfully document any of the returned fields. At the same time we
can't even meaningfully provide any form of API stability for the filed
*field
names.
Modify the documentation for the 'VIR_DOMAIN_STATS_VM' group both in the
API docs and in the virsh man page to reflect that and disclaim any form
of stability guarantees we provide normally.
Fixes: 8c9e3dae142
Signed-off-by: Peter Krempa <pkrempa@xxxxxxxxxx>
---
docs/manpages/virsh.rst | 36 ++++++++++++++++++++++++++++++++++--
src/libvirt-domain.c | 26 +++++++++++++++++++++++++-
tools/virsh-domain-monitor.c | 2 +-
3 files changed, 60 insertions(+), 4 deletions(-)
Reviewed-by: Ján Tomko <jtomko@xxxxxxxxxx>
Jano
