“Cardinality” is a mathematical term: it’s *the number of elements in a set*... boring! So why tf does anybody care??
Well, because people think they need it, then suddenly, "$$$$$$$."
0/ When large eng orgs rely on metrics for both monitoring *and* observability, they struggle with cardinality.
This is a thread about “the two drivers of cardinality.” And which one of those we should kill. :)
🧵👇
“Cardinality” is a mathematical term: it’s *the number of elements in a set*... boring! So why tf does anybody care??
Well, because people think they need it, then suddenly, "$$$$$$$."
E.g., when I was working on Monarch at Google, there was a single gmail metric that became over 300,000,000 (!!!) distinct time series. In a TSDB, that cardinality is the unit of cost.
So again, “$$$$$$$.”
A) Monitoring: more detailed *health measurements*
B) Observability: more detailed *explanations of changes*
Let’s take these one at a time…
Consider an RPC metric that counts errors. You need to independently monitor the error rate for different methods. And so – voila – someone adds a “method” tag, and now there’s 10x the cardinality for that metric.
Put another way, you might rightly have different error budgets for different RPC methods, so their statistics must be separable.
This is the real culprit! And, frankly, should be abolished. :) Metrics cardinality is the wrong way to do observability – to explain changes.
More on that…
But this is unsustainable: each incident reveals a new failure mode, devs keep adding tags, and before long your metrics bill is out of control.
Distributed systems can fail for a staggeringly large number of reasons. *You can't use metrics cardinality to isolate each one.*
Understanding change is the central problem of observability. Effective workflows might *start* with metrics, but they must pivot towards a multi-telemetry, multi-service guided analysis.
PPS: If you’d like to discuss/debate/request-more-detail any of the above, reply to this thread or DM me!
0/ I\u2019m tired of hearing about observability replacing monitoring. It\u2019s not going to, and that\u2019s because it shouldn\u2019t.
— Ben Sigelman (@el_bhs) January 13, 2021
Observability will not _replace_ monitoring, it will _augment_ monitoring.
Here\u2019s a thread about observability, and how monitoring can evolve to fit in: \U0001f447 pic.twitter.com/lhb1WmKKMF
More from Society
1/OK, data mystery time.
This New York Times feature shows China with a Gini Index of less than 30, which would make it more equal than Canada, France, or the Netherlands. https://t.co/g3Sv6DZTDE
That's weird. Income inequality in China is legendary.
Let's check this number.
2/The New York Times cites the World Bank's recent report, "Fair Progress? Economic Mobility across Generations Around the World".
The report is available here:
3/The World Bank report has a graph in which it appears to show the same value for China's Gini - under 0.3.
The graph cites the World Development Indicators as its source for the income inequality data.
4/The World Development Indicators are available at the World Bank's website.
Here's the Gini index: https://t.co/MvylQzpX6A
It looks as if the latest estimate for China's Gini is 42.2.
That estimate is from 2012.
5/A Gini of 42.2 would put China in the same neighborhood as the U.S., whose Gini was estimated at 41 in 2013.
I can't find the <30 number anywhere. The only other estimate in the tables for China is from 2008, when it was estimated at 42.8.
This New York Times feature shows China with a Gini Index of less than 30, which would make it more equal than Canada, France, or the Netherlands. https://t.co/g3Sv6DZTDE
That's weird. Income inequality in China is legendary.
Let's check this number.
2/The New York Times cites the World Bank's recent report, "Fair Progress? Economic Mobility across Generations Around the World".
The report is available here:
3/The World Bank report has a graph in which it appears to show the same value for China's Gini - under 0.3.
The graph cites the World Development Indicators as its source for the income inequality data.
4/The World Development Indicators are available at the World Bank's website.
Here's the Gini index: https://t.co/MvylQzpX6A
It looks as if the latest estimate for China's Gini is 42.2.
That estimate is from 2012.
5/A Gini of 42.2 would put China in the same neighborhood as the U.S., whose Gini was estimated at 41 in 2013.
I can't find the <30 number anywhere. The only other estimate in the tables for China is from 2008, when it was estimated at 42.8.
Two things can be true at once:
1. There is an issue with hostility some academics have faced on some issues
2. Another academic who himself uses threats of legal action to bully colleagues into silence is not a good faith champion of the free speech cause
I have kept quiet about Matthew's recent outpourings on here but as my estwhile co-author has now seen fit to portray me as an enabler of oppression I think I have a right to reply. So I will.
I consider Matthew to be a colleague and a friend, and we had a longstanding agreement not to engage in disputes on twitter. I disagree with much in the article @UOzkirimli wrote on his research in @openDemocracy but I strongly support his right to express such critical views
I therefore find it outrageous that Matthew saw fit to bully @openDemocracy with legal threats, seeking it seems to stifle criticism of his own work. Such behaviour is simply wrong, and completely inconsistent with an academic commitment to free speech.
I am not embroiling myself in the various other cases Matt lists because, unlike him, I think attention to the detail matters and I don't have time to research each of these cases in detail.
1. There is an issue with hostility some academics have faced on some issues
2. Another academic who himself uses threats of legal action to bully colleagues into silence is not a good faith champion of the free speech cause
How about Selina Todd, Kathleen Stock, Jo Phoenix, Rachel Ara, Sarah Honeychurch, Michele Moore, Nina Power, Joanna Williams, Jenny Murray, Julia Gasper ...
— Matt Goodwin (@GoodwinMJ) February 17, 2021
Or is it only Eric you pop at?
Are they all making it up too Rob?
Are they "beyond parody"? https://t.co/drQssTD0OL
I have kept quiet about Matthew's recent outpourings on here but as my estwhile co-author has now seen fit to portray me as an enabler of oppression I think I have a right to reply. So I will.
I consider Matthew to be a colleague and a friend, and we had a longstanding agreement not to engage in disputes on twitter. I disagree with much in the article @UOzkirimli wrote on his research in @openDemocracy but I strongly support his right to express such critical views
I therefore find it outrageous that Matthew saw fit to bully @openDemocracy with legal threats, seeking it seems to stifle criticism of his own work. Such behaviour is simply wrong, and completely inconsistent with an academic commitment to free speech.
I am not embroiling myself in the various other cases Matt lists because, unlike him, I think attention to the detail matters and I don't have time to research each of these cases in detail.
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Strangle selling. ( I am doing mostly in weekly Bank Nifty)
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Nothing big deal in that.
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Used 20% capital@44 each
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Assalam Alaiki dear Sister in Islam. I hope this meets you well. Hope you are keeping safe in this pandemic. May Allah preserve you and your beloved family. I would like to address the misconception and misinterpretation in your thread. Please peruse the THREAD below.
1. First off, a disclaimer. Should you feel hurt by my words in the course of the thread, then forgive me. It’s from me and not from Islam. And I probably have to improve on my delivery. And I may not quote you verbatim, but the intended meaning would be there. Thank You!
2. Standing on Imam Shafii’s quote: “And I never debated anyone but that I did not mind whether Allah clarified the truth on my tongue or his tongue” or “I never once debated anyone hoping to win the debate; rather I always wished that the truth would come from his side.”
3. Okay, into the meat (my love for meat is showing. Lol) of the thread. Even though you didn’t mention the verse that permitted polygamy, everyone knows the verse you were talking about (Q4:3).
4. Your reasons for the revelation of the verse are strange. The first time I came across such. I had to quickly consult the books on the exegeses or tafsir of the Quran written by renowned specialists!
A lot of things Muslims do now and claim as Islamic rule is actually a culture that Islam curtailed or tried to perfect.
— Sule Nana (@izesule) January 2, 2021
Let's talk polygamy.
Islam didn't come and say, "oh men, marry four wives"
No.
Polygamy was in existence, long before the coming of Islam.
1. First off, a disclaimer. Should you feel hurt by my words in the course of the thread, then forgive me. It’s from me and not from Islam. And I probably have to improve on my delivery. And I may not quote you verbatim, but the intended meaning would be there. Thank You!
2. Standing on Imam Shafii’s quote: “And I never debated anyone but that I did not mind whether Allah clarified the truth on my tongue or his tongue” or “I never once debated anyone hoping to win the debate; rather I always wished that the truth would come from his side.”
3. Okay, into the meat (my love for meat is showing. Lol) of the thread. Even though you didn’t mention the verse that permitted polygamy, everyone knows the verse you were talking about (Q4:3).
4. Your reasons for the revelation of the verse are strange. The first time I came across such. I had to quickly consult the books on the exegeses or tafsir of the Quran written by renowned specialists!
