4 ms·

AIUI the minimum latency on these is always measured in milliseconds, with 6-7ms apparently commonplace, which you're going to immediately feel using e.g. a blo

by dmw_ng 3y ago

AIUI the minimum latency on these is always measured in milliseconds, with 6-7ms apparently commonplace, which you're going to immediately feel using e.g. a block or network storage protocol. No references, but did look at moca for exactly the same reason a few months back. The physical size of the models I looked at also suggested you'd want to check power consumption before stuffing a home full of them - custom devices in a small market segment often drink electric. I'd much prefer a consistent <1ms latency 10 Mbit connection than 10ish ms gigabit with 100ms spikes when next door boils their kettle, etc.

godman_8 3y ago
If you’re not using any splitters and zero to a few couplers you can expect latency to be ~3ms with the model OP is using. You can easily achieve 1Gbps using NFS with 3-10ms of latency as long as the underlying hardware can support it. I would avoid doing block storage even over ethernet though, that should be reserved for DAC or fiber. These particular adapters are rated for 10W (5V/2A) and I doubt they use all of that. I haven’t seen any noticeable latency spikes using these either but your mileage will vary depending on your cabling and connections (especially older pre-digital cable splitters.)
- Schnitz 3y ago
  Moca is a fantastic option if you have a good quality coax run, ideally point to point without splitters. For example a lot of people at some point pulled coax from wherever the cable enters the house to their living room. Now when you get fiber, the fiber probably enters the house in the same spot as the coax does. You can repurpose the coax run to keep your media center hardwired, as a wifi backhaul, etc. and in those use cases (streaming, wifi, etc) the additional 5ms of latency are IMHO irrelevant. Of course, if you can run a new cable with ease, nothing will beat high quality Cat 6. A lot of us just don't have that options, lack of crawl space or attic, etc.
runjake 3y ago
I have the same set of ScreenBeam MoCA adapters that are in the article and I get <=1ms. I do not have any other signal on the coax run I'm using. Most home users aren't going to really notice or care about a 6-7ms latency for even network file protocols. They're probably using Wi-Fi anyway.
mdasen 3y ago
The average latency for MoCA 2 devices is 3.5ms which is half what you say the "minimum latency" is. The latency on my WiFi averages 7ms. So it's likely going to be better than a WiFi connection. My MoCA devices don't use crazy amounts of electricity either. It could also depend on where you are. In the US, homes often have quite good coax wiring. That might not be the case in many parts of the world. > I'd much prefer a consistent <1ms latency 10 Mbit connection than 10ish ms gigabit with 100ms spikes when next door boils their kettle, etc. Honestly, this just feels like FUD. You've made up a scenario with latency numbers that are wrong claiming with zero support or evidence that a neighbor boiling their kettle will make a connection bad. It sounds like you briefly looked at MoCA, never tried it, but formed a very strong opinion about it based on basically nothing.
- dmw_ng 3y ago
  > but formed a very strong opinion about it based on basically nothing. 3.5 ms is between 5x - 53x worse than what you'd see out of gigabit ethernet, depending on the quality of the equipment, but even at the low end this is absolutely something noticeable in any application heavy on round-trips (such as those mentioned). Nothing breaks my focus more quickly than an unpredictably slow or janky UI, it is far from a made up scenario, just open an explorer window pointing at an SMB share with a few hundred JPEGs with uncached thumbnails and you've already hit it. I'd much prefer consistency of a slower network than usability that evaporates at random, else what is the point of preferring a wired network over wireless in the first place? FWIW, listing a directory or opening a single file over SMB is at least 4 round-trips, that's 14 ms burned on lag just for a single thumbnail, in the best case, and it only multiplies from there.
thehappypm 3y ago
Umm, what? MoCa devices are very small and use negligible power. They also introduce far less latency than WiFi.

by dmw_ng 3y ago

godman_8 3y ago

If you’re not using any splitters and zero to a few couplers you can expect latency to be ~3ms with the model OP is using. You can easily achieve 1Gbps using NFS with 3-10ms of latency as long as the underlying hardware can support it. I would avoid doing block storage even over ethernet though, that should be reserved for DAC or fiber. These particular adapters are rated for 10W (5V/2A) and I doubt they use all of that. I haven’t seen any noticeable latency spikes using these either but your mileage will vary depending on your cabling and connections (especially older pre-digital cable splitters.)

Schnitz 3y ago
Moca is a fantastic option if you have a good quality coax run, ideally point to point without splitters. For example a lot of people at some point pulled coax from wherever the cable enters the house to their living room. Now when you get fiber, the fiber probably enters the house in the same spot as the coax does. You can repurpose the coax run to keep your media center hardwired, as a wifi backhaul, etc. and in those use cases (streaming, wifi, etc) the additional 5ms of latency are IMHO irrelevant. Of course, if you can run a new cable with ease, nothing will beat high quality Cat 6. A lot of us just don't have that options, lack of crawl space or attic, etc.

runjake 3y ago

I have the same set of ScreenBeam MoCA adapters that are in the article and I get <=1ms. I do not have any other signal on the coax run I'm using. Most home users aren't going to really notice or care about a 6-7ms latency for even network file protocols. They're probably using Wi-Fi anyway.

mdasen 3y ago

The average latency for MoCA 2 devices is 3.5ms which is half what you say the "minimum latency" is. The latency on my WiFi averages 7ms. So it's likely going to be better than a WiFi connection. My MoCA devices don't use crazy amounts of electricity either. It could also depend on where you are. In the US, homes often have quite good coax wiring. That might not be the case in many parts of the world. > I'd much prefer a consistent <1ms latency 10 Mbit connection than 10ish ms gigabit with 100ms spikes when next door boils their kettle, etc. Honestly, this just feels like FUD. You've made up a scenario with latency numbers that are wrong claiming with zero support or evidence that a neighbor boiling their kettle will make a connection bad. It sounds like you briefly looked at MoCA, never tried it, but formed a very strong opinion about it based on basically nothing.

dmw_ng 3y ago
> but formed a very strong opinion about it based on basically nothing. 3.5 ms is between 5x - 53x worse than what you'd see out of gigabit ethernet, depending on the quality of the equipment, but even at the low end this is absolutely something noticeable in any application heavy on round-trips (such as those mentioned). Nothing breaks my focus more quickly than an unpredictably slow or janky UI, it is far from a made up scenario, just open an explorer window pointing at an SMB share with a few hundred JPEGs with uncached thumbnails and you've already hit it. I'd much prefer consistency of a slower network than usability that evaporates at random, else what is the point of preferring a wired network over wireless in the first place? FWIW, listing a directory or opening a single file over SMB is at least 4 round-trips, that's 14 ms burned on lag just for a single thumbnail, in the best case, and it only multiplies from there.

thehappypm 3y ago

Umm, what? MoCa devices are very small and use negligible power. They also introduce far less latency than WiFi.