I'm sure I've seen dcmds that consume output from others.

if nothing else, i would think we could add something to do that

It looks fairly straightforward to use `mdb_eval()` - xhci.c has an example of the kind of thing.

yeah..

if i can ever get some free time, i'm going to try to do something.. if only so I don't have to remember it :)

we had a dump where (among other things) txg syncing was taking a long time as it was waiting to acquire a rrwlock as writer

and was able to track it down to a zfs diff operation holding things up

(and was reminded about the general unfortunate lack of backpressure in the zio pipeline)

congrats to the folks from oxide: oxide.computer/blog/our-100m-series-b

jbk: so much for "Hence, we do not starve writers"...

(found at the end of the big theory statement in rrwlock.c)

i guess it depends if holding up a txg sync for 4+ minutes is 'starving' or not :)

we've had a lot of issues that ultimately come back to 'the zio pipeline doesn't do backpressure'

though in this case I think it's zfs diff is going full throttle and just holding the lock for a long time

yeah, the assumptions about forward progress all assume relatively short hold times on read locks.

in other cases, you can basically create zio_t's and stuff them into the zio pipeline until it's _completely_ exhausted all of your kernel memory (even if you have hundreds of GB of ram)

fixing that unfortunately is a big lift

Seems like Oxide will 'premiere' some/new - Speaking Loudly in the Datacenter - Oxide Tour on youtube. youtu.be/iBHos6ZRrIg I hope I don't get kicked for sharing youtube video.. :P

Oh it is about Oxide 100M series B.. oxide.computer/blog/our-100m-series-b

I wonder what happens if you shout into an Oxide ¿whatever they call their units.

I believe they're all SSD storage so .. nothing?

Maybe those enlarged fans will change their RPM a little? I was kind a hoping someone would shout again. It was Brendan Gregg originally.

run a big hollywood wind machine at the rack to spin the fans backwards and really upset the service processors?

Long, long ago, early in my career, management decided to cancel support for one of the main department computers.

A few weeks later a lightning strike spun all the platters backwords.

They decided to surplus the system instead of paying to repair it.

I'm still sad about that.

there's an old saying 'the bitterness of poor quality remains long after the sweetness of low price is forgotten'... while not quite the same thing, a similar sentiment probably applies...

at a previous job, one of the managers had that printed out and on the wall in a conference room frequently used by our group... as a big of a passive aggressive prod to our IT director :)

he had a compulsory need to feel like he was always getting a deal

so no matter how good of a price it was, he would _always_ refuse the first quote from a vendor

even if the resulting delay ended up costing more than whatever the savings was

[illumos-gate] 17519 nvme panics on device with no namespaces -- Robert Mustacchi <rm⊙fo>

no names man, no names