Notices by Howard Chu @ Symas (hyc@mastodon.social)

@clive @ariadne @slyecho @dalias I think the lawnmower I used back in Michigan had more power than 2hp. ...

@dalias @ariadne If you're talking about a vehicle capable of carrying 4 occupants, I suspect the 0-100km/h acceleration time would be so slow you could never safely enter a major highway from a feeder road.

@dalias @ariadne the surface area of a vehicle isn't enough for panels that can produce enough power to produce a useful range. Cars would have to shrink by an order of magnitude for that to be possible, like with the Sunraycer which only weighed 265kg https://en.wikipedia.org/wiki/Sunraycer

You can get about 1500W if you cover the entire surface area of a car with panels. I.e., basically 2hp, which won't even get you moving on a flat road.

A google alert just drew my attention to some disinfo about #LMDB over on twitter. Since I no longer have an account there, I can't address it directly. But for one,

Nobody has been hawking LMDB for "more than 3 decades" - I only began writing it in June 2011.

https://x.com/sunbains/status/1853869698875859119

"LMDB doesn't support vacuum, DB file can only grow"

https://x.com/Horusiath/status/1854043603942748162

Other DBs like SQLite and MySQL etc need vacuum because they don't have true delete operations. Their delete just sets a flag on a record, making it a "tombstone", but leaves the record intact in the DB. All these tombstones accumulate over time and must be periodically vacuumed to keep the DB from growing infinitely.

LMDB actually deletes records immediately, it doesn't use tombstones, so it needs no vacuum.

Also, #LMDB outperforms all other DBs especially with memory pressure. Particularly because you must finely tune the caches of other DBs, and your tuning all goes out the window if system usage spikes unexpectedly. In those cases your tuning can become a pessimization, while LMDB just keeps running smoothly. See the tests here http://www.lmdb.tech/bench/ondisk/

https://x.com/sujayakar314/status/1853867598125162564

I knew the quality of discourse on twitter had taken a plunge but geeze guys. Get a clue. And btw, quit using that site, all you're doing is feeding trump and elon musk and they're both pretty well overfed already.

And this one, OMFG.

https://x.com/baotiao/status/1853889937063760316

"RocksDB has a more simple API. LMDB doesn't seem designed specifically as a KV storage engine"

This guy has absolutely no friggin idea what he's talking about. #LMDB is the most fundamentally distilled essence of a transactional KV storage engine. #RocksDB is a Rube Goldbergian Frankenstein's monster that even its authors admit they don't know how to tune or optimize correctly.

So yes it's true that LMDB doesn't have any explicit operation to reclaim dead space - that's because it doesn't need it. It also tracks all freed pages and reuses them as soon as it's safe to do so, so while "the file can only grow" in reality it only grows as fast as you add data to the DB, and will automatically reuse space whenever you delete data from the DB.

@br00t4c in local elections? Are they considered legal residents of the city/county they're imprisoned in? Wouldn't they just vote for DAs and judges who would release them from prison?

@wilfredh in my human factors course in ~1989, the research we read all said cursor keys were #1 for efficiency when navigating text. #2 was trackballs. Mice were dead last. Of course Steve Jobs had to popularize mice...

Mice lose by a huge margin because they require you to pick up your hand and move (possibly multiple times) and then re-find your position on keyboard.

Trackballs also allow higher precision fine motion as well as coarse motion.

@inthehands hm, it was longer ago than I thought..... https://www.reddit.com/r/compsci/comments/p9sqi/sorting_routines_developed_by_genetic_algorithms/

@inthehands just reminded me of the sort routine produced by a genetic algorithm some years ago, that made the news because "nobody understood how it worked". Can't find a reference now.

Y'know, when I was learning my way around Unix system programming, I was told "the source code is the documentation" and that worked for me. When I wanted to find out if there was a C library function to do what I wanted, or how it worked, I read the C library source code. When I didn't like how the library worked I changed it and recompiled it.

After something like 30 years hacking with #OpenSSL, I think it's time to part ways. The #OpenLDAP Project will be deprecating OpenSSL support and recommending some other crypto library in the near future. https://github.com/openssl/openssl/issues/25294#issuecomment-2391707060

I guess DMARC works. I'm now getting daily reports from various mailers that have rejected spurious emails using my personal domain.

@dalias @Qyriad my bank's app is worse. Pretty sure it checked for my bootloader ever being unlocked. Even after I removed root and relocked bootloader, it still complains the phone is rooted.

Either that, or there's another rootkit hiding out on the phone that I need to find...

@br00t4c hmmmm. Mixed feelings on this one, being from California, and knowing too much about Avalanche blockchain...

@eliasr the ones currently in my house are triggered by steam escaping the bathroom after a hot shower. Maybe the steam is condensing on the sensor, not really sure what the triggering mechanism is.

Hey lazyweb - are modern smoke detectors capable of distinguishing steam (e.g. from a bathroom shower) from actual smoke?