Air New Zealand Is Bringing Lie-Flat Beds to Economy

again

I flew in a SkyCouch once

I liked it

i would like a sky couch on every flight

yeah I flew 'first class' west to east coast and it was not

whose coasts

USA

flying is fundamentally horrible. the least they can do is provide alcohol, entertainment, food, and a bed to make it less miserable

yeah

i tend to fly first and have a couple airline branded credit cards to get a little extra smile out of the attendants

Morning

Good morning Mr Roux

> Observe the XEvent data. It will take about 10mins to see XXXX event which means the final DOP setting to achieve stability.

only 10 minutes for dop feedback to work eh

source

I wouldn't read too much into that

i still haven't seen it kick in

Me either, but then I haven't tried at all

I half-watched a demo once

this feels silly at this point

i'm not even seeing ineligibility messages

So DOP feedback is a lie?

@ErikDarling Is DOP_FEEDBACK on at the database level? 160 compat?

yeah

and you're running test queries in the context of that database with QS on and running?

you got it

sounds like you might be experiencing

local factors

@ErikDarling how's maxdop set? any RG going on?

8 server wide, nothing for database scoped

i'm not smart enough to use rg

local instance or container?

what the fuck is a container

@ErikDarling there was some debate about how the various maxdop options should interact, have you tried setting it to zero

scribbles down "local instance"

😀

no, the limited demo i saw didn't list that as a factor

dop 0 let's go

it shouldn't make a difference, but who knows

instructions at github.com/microsoft/bobsql/blob/master/demos/sqlserver2022/IQP/… if you need them

still not even getting negative feedback

weird

ah well

probably insufficient skewness

how should it work in theory?

largely undocumented

> Identifies parallelism inefficiencies for repeating queries, based on elapsed time and waits. If parallelism usage is deemed inefficient, DOP feedback lowers the DOP for the next execution of the query, from whatever is the configured DOP, and verifies if it helps. Requires Query Store enabled.

So to test the repro you need a query that has inefficient parallelism, to begin with. Run it a couple of times and wait for it to fix itself?

@ErikDarling is that demo you saw public?

@Zikato afaik

do you have a link?

click on the link paul just posted and navigate back a step or two in the github repo

@ErikDarling no trace flags enabled in the 12xxx range?

sorry, I've missed that. Thank you

@PaulWhite yeah nah this is pretty vanilla

ctfp isn't even set

@ErikDarling Getting a fresh compilation each time? Tried checkpoint & drop clean buffers to introduce some non-parallel waits?

Assuming you're getting much in the way of parallelism waits in the first place

One of the exchange spill demos perhaps

definite plan reuse, no drop clean buffers though

i'm trying to find a column with sufficient skewness that doesn't trigger psp

hrm

the skewness was a joke

skew you

The goal of DOP feedback is is to increase concurrency and reduce waits, even if it slightly increases elapsed time.

yeah

i'm hip to the marketing

just can't repro, hahaha

or demo

i've tried telling sql server that i was a fashion model in the 90s

or rather, i can't get a working demo in SO2013 just yet

@ErikDarling perhaps it didn't believe you

don't see how that's possible

i showed it my mole

hm not that then

so you have demo'd in other databases, just not SO2013?

i haven't tried the wwi demo yet

bob's script to inflate the table to provide sufficient skewness is ridiculous

@ErikDarling how much have you practiced your blue steel look?

20mm row loop

@Lamak don't test me it will cut you in half

> set

@ErikDarling sounds about right

@ErikDarling did you see the perf improvement suggestion showcasing generate_series

@PaulWhite top form today eh

@ErikDarling github.com/microsoft/bobsql/pull/34/commits/…

I don't know if I linked that right, I don't really github

or dock

my left eyelid has begun twitching

🤨 (face with raised eyebrow)

so this demo proc returns 20mm rows sorted over and over again

what the hootin' hollerin' heck is going on here

yeah kinda wacky eh

I'll try the demos as well, you got me intrigued

i am particularly stewed over this situation

containers can help with that

i think i'll go open a bank account i don't need to get a safe deposit box convenient to me

I swear to god if Windows asks me one more time to link my android phone...

@PaulWhite but have you thought about it?

Is that Windows 11? I've never got that prompt

i get it all the time

I tried it once...am I crazy or is it just a simple casting of the phone's screen?

@Zikato 10

@Lamak I might've done if I owned an android

@ErikDarling I've just noticed. This will take ~13 mins to execute

No one running the optimised version

I wasn't paying attention. I just read the instructions and went to make the dinner

After 8 minutes of running it's a sunk cost anyway

sounds like a fallacy

@Lamak you tried Windows once? ;)

@PaulWhite yeah it is a dick move

ho ho

🥁

@ypercubeᵀᴹ yes. After that I just adopted it

It's not a very realistic demo though

Scratch that. People in glass houses…

I am the proud owner of a safe deposit box and a phone that doesn’t have a broken screen and several cocktails