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Charity Majors
@mipsytipsy
, 3 tweets, 1 min read Read on Twitter
Pro Tip: when a vendor claims to handle high cardinality, don't rejoice before you ask:

* what do they mean by "handle"?
* can you break down by a hi-card dimension?
* can you break down by multiple? how many?
* do you have to index that field in advance?
* describe perf hit?
* what data types can be hi-card?
* what are the limits on those fields?
* what operations can you run on them?
* describe implications to your storage footprint,
* and costs
* what is the tested upper limit to cardinality?
* must you define schema up front?
* how wide can it be?
there are so many sneaky ways to lie with data, tests, and cute marketing slogans ("Infinite Cardinality!")

more like infinite marketing budget, lol
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More from @mipsytipsy see all

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Charity Majors
@mipsytipsy
"There are only two things your organization should be spending time on: making your customers happy, or making your people happy.". -@lizthegrey at o11y meetup. #velocityconf
"CI/CD is great, and it's only the first step. We need to learn how to get our code into production faster, understand it better, and use the same tools for pre-prod and production"

(my phone camera broke so all I can do is selfies now, sorry)
speaking of which, here is my summary of San Jose today
Read 3 tweets
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Charity Majors
@mipsytipsy
never forget that i am not a mathematician or a capital-e Engineer, i am ops to the bone. the only definition i care about is the one that helps me understand ✨real production systems✨. theory schmeary.

(two days later, she remembers to complete her thought)
i don't know how the theory of systems controllability and its mathematical dual, systems observability, would look when applied to modern production systems.

to me it's like asking how one might calculate the nth order derivative of a hairball you found under your bed.
i do know what characteristics you need in *reality* to understand what's happening on the internals of your systems, by observing them from the outside:

* raw events of arbitrary width
* aggregate at read time
* no indexes r--

... aw hell i've given this list so many times
Read 4 tweets
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Charity Majors
@mipsytipsy
i keep forgetting to link to this longer piece. it tells the tale of how we tested a script to *terminate our entire infra and replace it with a newer OS* in prod.

"spend less time on what doesn't matter, more on what does. Test In Prod." techbeacon.com/app-dev-testin…
but hey: the biggest reason "Don't Test in Prod" was a cardinal principle for years was because all you had was monitoring tools and aggregates, and you legit couldn't tell at a hi-res granularity what the subtle effects of your tests were.

if you're flying blind, *don't do it.*
observability -- the way i define it, which is NOT how every other vendor out there defines it -- requires the ability to slice and dice down to raw events, and group by any combination of multiple high cardinality dimensions.

so you can see what the loving hell you're doing.
Read 5 tweets

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Angela Davis
@TheKitchenista
Pro tip... that chicken you’re putting on the grill tomorrow? Salt it aggressively including under the skin and drown it in buttermilk. Drain the milk tomorrow & season the chicken with your spice rub before grilling/smoking.
I’ve always been an advocate of buttermilk brines. 🥰
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Donie O'Sullivan
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#BREAK This evening Facebook suspended a group of Russian-backed Facebook pages with millions of video views, some targeting American millennials. The pages didn’t disclose their Russian ties (but Facebook’s rules don’t say they have to). @CNN

cnn.com/2019/02/15/tec…
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The pages appear to have fallen into a gray area for Facebook.
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Jen Spindel
@jsspindel
Pro tip: Don't start a discussion of data set coding 15 minutes before you have to go teach. Here's my attempt at a re-cap:

1/ @ProfPaulPoast starts off by discussing teaching grad students about coding decisions, and the difficult decisions:
2/ great discussion bt @DenisonBe, @sbmitche, @KSchultz3580, @BridgetCoggins, @dhnexon abt difficulties of coding decisions, and the way that datasets might be (a) a product of their time, and (b) get reified when imported into other large data projects.
3/ @sbmitche crucially highlights the importance of reading codebooks, and @KSchultz3580 notes that there has been a useful move toward providing fuller documentation of coding decisions.

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Lucid Trader
@MrAaronKlein
Pro tip: If I gave you an entry yesterday, I expect an all day run in that same direction today.

Does it always work?

Obviously not.

Have a plan, lock your gains, stop ITM & give nothing back by chasing chop.

DM me for more.
$AMD do we have to sit here watching this, guessing... when we bought under $20 yesterday and already locked gains?

I’m just waiting for an afternoon NHOD (or lunch)

So WHY watch THIS?

Do what we want or stop us ITM after paying us to enter #tradernap
$TSLA read the thread.

You already know we shorted $351 when nobody saw it coming and I gave you the final short exit yesterday after multiple trades down.

WHY watch this chop?

Already locked gains this am & reloaded.

Paid to enter.
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GeePaw Hill
@GeePawHill
TDD Pro-Tip: Because the power of TDD is operational rather than artifactual, test-before provides several benefits over test-after.
Sometimes folks propose the writing of tests after the code is written. The idea here is that the point of the game is to have the tests, and that it makes no difference whether we do them before we write the code or after.
This idea is flawed: it centers TDD around the artifact -- the made test -- rather than the triple-balance of made-making-maker.
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Being Ulti
@being_ulti
Alrighty - time to talk about mental toughness and emotional intelligence. I'll also talk about how to be a good teammate. All three of these were lessons that I've learned over the past three years, starting with my time playing for @SeattleSockeye .
This is a hard one for me and I've been pushing it off, at least sub-consciously, until now. I'll do my best to be honest and sincere. I'll also try to keep the typos to a minimum and keep things in chronological order. This'll probably be a long one. Good thing most are asleep!
On Monday I told my story up through the end of playing for @PrideofNY . In that thread I mentioned that I tore my [right] ACL. It was a complete tear (you can partially tear it) without any meniscus damage.
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