[storage] define statistics object

[glimchb]

Signed-off-by: Boris Glimcher Boris.Glimcher@emc.com

[glimchb]

@ekaley FYI

[llabordehpe]

Shoudn't these be 64-bit counters ?

[glimchb]

I guess, we can make them 64 bit. opened #221

[llabordehpe]

Not sure I understand why there are VolumeStats in the NVMe subsystem, controller and namespace objects. Are the stats for the subsystem an aggregate for all volumes/namespaces currently (or ever) attached to that subsystem, versus the namespace stats which are for this volume only ?

[glimchb]

Not sure I understand why there are VolumeStats in the NVMe subsystem, controller and namespace objects. Are the stats for the subsystem an aggregate for all volumes/namespaces currently (or ever) attached to that subsystem, versus the namespace stats which are for this volume only ?

exactly, aggregate

@llabordehpe you can also refer to Marvell https://github.com/opiproject/opi-marvell-bridge/blob/main/mrvl_nvme_json.rpc_methods.pdf

• mrvl_nvm_subsys_get_info
• mrvl_nvm_ctrlr_get_stats
• mrvl_nvm_ns_get_stats

[jainvipin]

I like this approach, where stats are associated clearly with the object itself at a given point in time i.e. it is clear and works for not so heavy stats users. I am commenting vis-a-vis OTEL as the method of exporting/streaming the stats.
To @llabordehpe's point it would good to document the desired behavior on the Volume stats in various objects where the object is embeded.

[glimchb]

I like this approach, where stats are associated clearly with the object itself at a given point in time i.e. it is clear and works for not so heavy stats users. I am commenting vis-a-vis OTEL as the method of exporting/streaming the stats.

Good topic to discuss, how exactly we want to stream telems from OTEL perspective. I would imagine we should compile DPU SDK with OTEL SDK and stream directly. So what we can do in OPI is to define the OTEL format and telems needed streaming...

To @llabordehpe's point it would good to document the desired behavior on the Volume stats in various objects where the object is embeded.

Agree 100%, documentation is lacking.