buybackoff (u/buybackoff)

buybackoff commented on Toothpaste made with keratin may protect and repair damaged teeth: study kcl.ac.uk/news/toothpaste... · Posted by u/sohkamyung

alyx · 10 days ago

Never heard of Novamin but doesn't look promising?

https://pmc.ncbi.nlm.nih.gov/articles/PMC7068624/

Conclusion Review shows that Novamin has significantly less clinical evidence to prove its effectiveness as a remineralization agent in treating both carious and non-carious lesion. Hence, better designed clinical trials should be carried out in the future before definitive recommendations can be made.

buybackoff · 10 days ago

Inetersting, the paper explain how remineralisation works and the role of F and fluoroapatite. This reminds me the recent Veritasium video about why Teflon is so strong - F chemical bonds are the strongest.

For Novamin alone, I've seen and understood the claims of sensitivity protection with hydroxyl-carbonate apatite (HCA). The paper explains it in 4.3. The layer is temporary and protects from acids, conserving the teeth tissue below.

But F is essential and my paste has it together with Novamin. It seems they may work well together. But the paper also explains that F works with saliva rich in minerals to repair the enamel. So if Novamin creates a strong layer, it may block access of F + saliva to enamel (my speculation, as in 4.2 they say "A clean tooth surface is required to access the mineral-deficient spot.").

So maybe a classical Ca+F paste is better overnight when no acid exposure is expected, but Novamin is nice in the morning before breakfast.

buybackoff commented on Toothpaste made with keratin may protect and repair damaged teeth: study kcl.ac.uk/news/toothpaste... · Posted by u/sohkamyung

safety1st · 10 days ago

I don't know what this new hairpaste does, but Novamin promotes re-enamelization of teeth, which is where mineral ions like calcium bond themselves to the tooth and fill in small pits and fissures. It's not regrowing actual enamel, it's probably not going to fill in any pits you can see with the naked eye, but it's a real and beneficial effect. Actually any fluoride toothpaste also does this, but Novamin may be a bit more effective at it.

buybackoff · 10 days ago

I had an impression that Novamin creates an artificial layer as strong as natural enamel, and fills tiny holes that are responsible for high sensitivity with this material that crystallizes with water contact. Then normal Ca+F mineralisation is orthogonal. Novamin itself contains Ca, can it really migrate from the crystals into the tooth tissue?

buybackoff commented on Toothpaste made with keratin may protect and repair damaged teeth: study kcl.ac.uk/news/toothpaste... · Posted by u/sohkamyung

majkinetor · 10 days ago

I use novamin but I can't feel a chemical reaction.

Have you noticed something more promising ? I am not sure, because I typically do not eat carbs.

buybackoff · 10 days ago

I feel it on the spot that was sensitive to cold, and that was the reason I looked for something new. The paste is of room temperature, so that feeling must be not a fluke. No idea if it actually works, F+Ca used to be enough.

buybackoff commented on Toothpaste made with keratin may protect and repair damaged teeth: study kcl.ac.uk/news/toothpaste... · Posted by u/sohkamyung

buybackoff · 10 days ago

The picture says "enamel-mimicking" and the text says "protective coating that mimics the structure and function of natural enamel", so it looks like a protective layer, not true repair. I've been using a paste with novamin lately, it also creates a protective layer and is also marketed as "repair". I like it and feel some heat when it contacts with teeth, so the chemical reaction must be working. But the marketing leaves a bad taste in the mouth.

buybackoff commented on lsr: ls with io_uring rockorager.dev/log/lsr-ls... · Posted by u/mpweiher

buybackoff · a month ago

A little offtop, but do you know a number in usecs that io_uring can save on enterprise grade servers, with 10G NICs, for socket latency overheads vs LD_PRELOAD when hardware supports that? Let's say it's Mellanox 4 or 5. My understanding is that each gives around 10us savings, maybe less. Based on some benchmarking, which was not focused on any of those explicitly but had some imprecise experiments. It also looks like they do not add up. Do you have a number based on real experience?

buybackoff commented on Aeron: Efficient reliable UDP unicast, UDP multicast, and IPC message transport github.com/aeron-io/aeron... · Posted by u/todsacerdoti

erikvanoosten · a month ago

It has been a while since I saw their presentation. What I remember is that Aaron has an insanely low delay even in the high percentiles, that is orders of magnitude better. Throughput for a large stream of data is probably similar to plain UDP. Please correct me if I remember wrong.

buybackoff · a month ago

It does have great tail latency. But it's not a silver bullet, but careful engineering. And you pay for the latency with spinning threads. It's the architecture that makes it to stand out. In the end, it's just the same old UDP sockets, not even io_uring at least in the free public version. But one can use LD_PRELOAD if hardware has this trick - but again, it's not specific to Aeron.

buybackoff commented on Aeron: Efficient reliable UDP unicast, UDP multicast, and IPC message transport github.com/aeron-io/aeron... · Posted by u/todsacerdoti

lll-o-lll · a month ago

> Relative latency savings cross-DC become less interesting the longer the distance, so there's nothing wrong with TCP there.

Long fat pipe sees dramatic throughput drops with tcp and relatively small packet loss. Possibly we were holding it wrong; would love to know if there is some definitive guide to doing it right. Good success with UDT.

buybackoff · a month ago

I would not recommend using Aeron on long fat pipes with a chance of packet loss for hight throughput. It was several years since I stress tested this, maybe there have been improvements. I saw some work on that in release notes after. But that was the worst case as recovery was slow.

I would think of UDP with redundant encoding / FEC, to avoid retransmits.

buybackoff commented on Aeron: Efficient reliable UDP unicast, UDP multicast, and IPC message transport github.com/aeron-io/aeron... · Posted by u/todsacerdoti

lowwave · a month ago

>Also, if one can leverage multicast that's nice, but not only clouds have it disabled, and Aeron works fine with unicast to N.

How did that happened? Seems multicast is already built in, just use that for massive broadcast. Is TCP used just so we can get an ACK that it is received. Seems multicast and UDP shouldn't be a problem if we just want massive people to listen in on it, but if we want to also track these people then that is another story.

From a user perspective, use UDP/multicast all the way. Let the client to request something if it is dropped or missing or otherwise just multicast for everything.

buybackoff · a month ago

I mean multicast is often disabled not only in the cloud DCs, but on-premises as well, intentionally for different reasons.

buybackoff commented on Aeron: Efficient reliable UDP unicast, UDP multicast, and IPC message transport github.com/aeron-io/aeron... · Posted by u/todsacerdoti

buybackoff · a month ago

One of the greatest things about Aeron is just the fact it exists. If one goes e.g. to StackOverflow or a place with the same patronizing attitude of "experts", they will tell you no one needs UDP, even in the same DC on reliable network, especially no one needs multicast. Any sane person should use TCP with a loop for multiple destinations, they would say, and one should measure before optimizing, they would say. But they themselves probably never had a chance to measure. Yet Aeron guys, who are real expert in low-latency systems, just delivered an ultra-fast thing that is quite simple in design.

Aeron latency histograms vs TCP are quite nice in the same DC on enterprise-grade networking hardware. But it really makes sense to use if a single-digit or low-double digit microsecond latency improvement on P50 is worth the effort. Or if the long tail with TCP is a dealbreaker, as Aeron has much nicer P99+ regardless of how well optimized a TCP setup is. Also, if one can leverage multicast that's nice, but not only clouds have it disabled, and Aeron works fine with unicast to N.

However, there are gotchas with threading and configuration overall. Cross-DC setup may surprise in a bad way if buffers are not configured to account for bandwidth-delay product. Any packet loss on high-latency network leads to a nasty NACK storm that is slow to recover under load. It's better to set the highest QoS and ensure the network is never dropping packets, e.g. calculate the real peak instant load vs hardware capacity. Relative latency savings cross-DC become less interesting the longer the distance, so there's nothing wrong with TCP there. Another note is that, e.g. ZMQ is slow not because of TCP but because of its internals, almost 2x slower for small packets than raw well-tuned TCP sockets, which are not that bad vs Aeron. Also, Aeron is not for sending big blobs around, the best is to use it with small payloads.

Aeron is designed with mechanical sympathy in mind by the guys who coined this term and have been evangelizing it for years, and it's visible. Lots to learn from the design & implementation (tons of resources on the web) even without using it in prod.

buybackoff commented on Someone at YouTube needs glasses jayd.ml/2025/04/30/someon... · Posted by u/jaydenmilne

buybackoff · 4 months ago

It's not the count if thumbnails, it's the algo that either does not work at all or works only for them. Average engagement and zero control. Paid or free, they do not care.