I guess most people don't have faster local network than an SSD can transfer.
I wonder though, for those people who do, does a concurrent I/O block device replicator tool exist?
Btw, you might want also use pv in the pipeline to see an ETA, although it might have a small impact on performance.
Besides, I don't think anyone really has a local network which is faster than their SSD. Even a 4-year-old consumer Samsung 970 Pro can sustain full-disk writes at 2.000M Byte/s, easily saturating a 10Gbit connection.
If we're looking at state-of-the-art consumer tech, the fastest you're getting is a USB4 40Gbit machine-to-machine transfer - but at that point you probably have something like the Crucial T700, which has a sequential write speed of 11.800 MByte/s.
The enterprise world probably doesn't look too different. You'd need a 100Gbit NIC to saturate even a single modern SSD, but any machine with such a NIC is more likely to have closer to half a dozen SSDs. At that point you're starting to be more worried about things like memory bandwidth instead. [0]
[0]: http://nabstreamingsummit.com/wp-content/uploads/2022/05/202...
Doesn't make sense at first glance. There's no head to move, as in an old-style hard drive. What else could make random write take longer on an SSD?
You can check literally any SSD benchmark that tests both random and sequential IO. They're both vastly better than a mechanical hard drive, but sequential IO is still faster than random IO.
So if large sequential writes mean that you only write full whole blocks, that can be done much faster than writing the same data in random order.
RMW cycles (though not in-place) are common for writes smaller than a NAND page (eg. 16kB) and basically unavoidable for writes smaller than the FTL's 4kB granularity
Any modern (last few decades) SSD has a lot of sauce on top of it to reduce this penalty, but random writes are still a fair bit slower - especially once the buffer of pre-prepared replacement pages runs out. Sequential access is also just a lot easier to predict, so the SSD can do a lot of speculative work to speed it up even more.
You might be surprised if you take a look at how cheap high speed NICs are on the used market. 25G and 40G can be had for around $50, and 100G around $100. If you need switches things start to get expensive but for the "home lab" crowd since most of these cards are dual port a three-node mesh can be had for just a few hundred bucks. I've had a 40G link to my home server for a few years now mostly just because I could do it for less than the cost of a single hard drive.
They're PCIe 3.0 x8 cards so they can't max out both ports, but realistically no one who's considering cheap high speed NICs cares about maxing out more than one port.