Integrate collectd with OpenBMC

[vishwa]

Hi,


On 7/22/19 10:00 PM, Brad Bishop wrote:
> On Thu, Jun 27, 2019 at 10:51:03PM -0700, Kun Yi wrote:
>> Hello there,
>>
>> In the context of reporting BMC performance metrics, my intern Gabriel
>> (cc'ed here) and I have started looking at integrating collectd as a
>> metrics collection tool on OpenBMC. We have got it running, which is
>> trivial, but the next question is how to report the data.
>>
>> We have thought about it and thinks implementing a D-Bus interface to be
>> the most flexible approach. At first, we could implement a snapshot
>> (instantaneos read) interface. It would then be fairly 
>> straightforward to
>> add them as Redfish/IPMI sensors.
>
> Just curious in what situations DBus was required?  In the design I 
> thought you had applications going right to librrd - where did that 
> fall down?
>

 From what I saw in the design template, librrd to be used to enable any 
daemon to make their data available to collectd.

The proposal here is to externally report the data collected. I 
understood it as; we going to have per plugin D-Bus APIs to report it. 
But looking at it again, I am not sure how is that achieved.

Kun, Do you have a flow schematic ?


>>
>> There are two ways to do this:
>> 1. Implement as a collectd "D-Bus" plugin [1]. Collectd supports writing
>> custom plugins which are C files calling the internal plugin APIs. Could
>> probably use sdbus to implement.
>>
>> + could potentially be upstreamed to collectd
>> - the code probably will live in a downstream fork first, and if it 
>> doesn't
>> end up upstream, maintaining could become an issue since collectd plugin
>> API is not guaranteed stable
>> - C
>>
>> 2. Implement as an interposer daemon that translates between one of the
>> formats that collectd supports (unix socket, plaintext, RRDTool..) to 
>> D-Bus
>>
>> + project could be purely OpenBMC
>> + can use sdbusplus
>> - another daemon
>>
>> Any advice on this? Currently we are leaning towards the first approach,
>> but do you agree the D-Bus plugin is general enough to be of interest to
>> the upstream collectd community?
>>
>> I can definitely reach out to the collectd group but just want to ask 
>> here
>> first :)
>>
>> [1] Collectd plugins:
>> https://collectd.org/wiki/index.php/Plugin_architecture
>> -- 
>> Regards,
>> Kun
>