Hello Xiao, When you say that the meaning of the metric will change, could you elaborate further? The PIP does not talk about what all labels you are proposing in this new metric, so maybe you can add more details in the PIP.
Here is what I understood from your PIP description. You will add a new metric `pulsar_subscription_back_log_size` which will have granularity of backlog size at a topic-subscription combination. Which means the general use of the metric would be like sum(pulsar_subscription_back_log_size) by (topic, subscription[, ...]) . If this understanding is correct, then when the config to enable this new metric is true, then these two expressions: *`sum(pulsar_storage_backlog_size) by (cluster, topic)`* and *`sum(pulsar_subscription_back_log_size) by (cluster, topic)`* will always result in the same value. The only difference is that the new metric will also allow you to do *`sum(pulsar_subscription_back_log_size) by (cluster, topic, subscription)`* to get value for each subscription of the topic. Regards On Fri, Dec 30, 2022 at 10:26 PM 萧 易客 <km...@live.com> wrote: > Hi Sharma, > > If a metric has different meaning with different config, it confuses user > cause they need to check the config before use it. It's not best practice > cause it's easy to made a mistake if user forgot or config changed. > For example, if user has multiple clusters with different config, the same > metric has different meaning on each cluser, it's add extra work to > maintaining alarm rule. > > Yike Xiao > > ________________________________ > 发件人: Girish Sharma <scrapmachi...@gmail.com> > 发送时间: 2022年12月31日 0:07 > 收件人: dev@pulsar.apache.org <dev@pulsar.apache.org> > 主题: Re: [DISCUSS] PIP-235: Add metric for subscription back size > > How about adding a new label subscription in the same metric? It should > also not break any existing usage of the metric as well for those only > aggregating on topic or cluster label. The documentation can clearly > mention that this is an addon on top of existing metrics. > > Please pardon my mistake as I am new to this mailing list, but if new > additions to the same metrics are not considered by default as a general > guideline in pulsar codebase, then this can go on its own new metric. It is > just that this new metric would then again need the same labels (cluster, > broker, topic etc) causing a lot of duplicate data. > In our in-house usage of pulsar, metrics finally flow into a central > platform and we have to be careful on the size (number of metrics and > labels) that we are ingesting into this platform. > > Regards > > On Fri, Dec 30, 2022 at 8:55 PM 萧 易客 <km...@live.com> wrote: > > > Hi pulsar community, > > > > Motivation > > Now we have pulsar_storage_backlog_size for topic backlog size, user can > > create an alarm rule like pulsar_storage_backlog_size > THRESHOLD, > > typically this alarm is going to notify corresponding subscription owner, > > but it need extra process to identify subscriptions that backlog size > > exceed the threshold. So we could add a new metric for subscription back > > size. > > > > For more detail, please read PIP-235 issue page [1] > > > > It's my first PIP, I'm looking forward to hearing what you think and open > > for any suggestions. > > > > [1]: > https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fapache%2Fpulsar%2Fissues%2F19112&data=05%7C01%7C%7C830f15a75a5e4834f0f808daea7ffc58%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638080132677757011%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=hNjo6llUJ0gbi3PTjXwcYAipQ3cTSWmzFWFJCr3auZc%3D&reserved=0 > > [ > > > https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fopengraph.githubassets.com%2Fabebee001c4e8297f9418e3b78bd77a854f26d1c4b73bfea5fb203251968a18e%2Fapache%2Fpulsar%2Fissues%2F19112&data=05%7C01%7C%7C830f15a75a5e4834f0f808daea7ffc58%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638080132677757011%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=p%2F7ZpaqFn5nJzVOP46cYjuN1KQZ0mhuiG8kUfJtkq7Q%3D&reserved=0 > > ]< > https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fapache%2Fpulsar%2Fissues%2F19112&data=05%7C01%7C%7C830f15a75a5e4834f0f808daea7ffc58%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638080132677757011%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=hNjo6llUJ0gbi3PTjXwcYAipQ3cTSWmzFWFJCr3auZc%3D&reserved=0 > > > > PIP-235: Add metric for subscription back size · Issue #19112 · > > apache/pulsar< > https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fapache%2Fpulsar%2Fissues%2F19112&data=05%7C01%7C%7C830f15a75a5e4834f0f808daea7ffc58%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638080132677757011%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=hNjo6llUJ0gbi3PTjXwcYAipQ3cTSWmzFWFJCr3auZc%3D&reserved=0 > > > > Motivation Now we have pulsar_storage_backlog_size for topic backlog > size, > > user can create an alarm rule like pulsar_storage_backlog_size > > > THRESHOLD, typically this alarm is going to notify cor... > > github.com > > > > > > > > Yike Xiao > > > > > -- > Girish Sharma > -- Girish Sharma
