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Comment by mjevans | Hacker News Reader

I'd use Backblaze a LOT more... if consumer ISPs in the US weren't pretty much monopoly BS. (Can you really call "up to" 12mbit down (and like 1mbit up max) VDSL a competitor to 1000mbit down ~30mbit up cable? Both of which are WAY TOO SLOW for backup up real workloads! Let alone the caps @.@)...

Also no, where I live is typical of American Surburbia, if anything it's actually slightly better than the median who suffer through Ex-GTE hell and cable ISPs so bad they make even comcrud look good.

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> Both of which are WAY TOO SLOW for backup up real workloads!

If you use half of a 30mbit upload for backing up, that's 5 terabytes a month. I think that covers a lot of real workloads.

Except that if you saturate your uplink you will also likely make your downlink sluggish.

And a user may not want to wait 20 hours for an operation to complete.

If maxing your upload slows down your download, or vice versa, its an issue with your router, anything sensible should put maximum priority on TCP acks and avoid the issue altogether.

ACK prioritization isn't always good for overall usability of an internet connection. It definitely shouldn't be used unless there's good FQ-style QoS active in both directions. Once you have that, if you're going to do anything special for ACKs, you should probably try ACK thinning before prioritizing ACKs over regular data transfers going in the same direction.

what is an example of when it is bad to do this.

If you have enough ACKs going upstream to start being a problem, you are most likely downloading a large file, and that traffic isn't particularly latency-sensitive in either direction. If you have something actually interactive that's also trying to use the same link (eg. VoIP), that traffic probably should be prioritized over a firehose of ACKs even if it will make the file download a bit slower. ACKs shouldn't be treated as any more important than the payload data they they are acknowledging. Low priority downloads should generate low-priority ACKs.

ACKs are generally so small its irrelevant, unless your bandwidth is ridiculously asymmetric (less than a 23:1 ratio 64B ACK vs 1500B packet) which even really crappy cable providers don't do.

It's a very real problem for many if not most surviving DSL connections. Cable has gotten a bit better in recent years, but 10:1 is still about the best you can normally expect, and 20:1 or 25:1 is still common for some of the higher speed tiers on cable. So ACKs can realistically be expected to take up half of your upstream bandwidth on common connection types. That's far from irrelevant unless you never transmit anything other than ACKs and HTTP GETs.

To be fair, the example we're responding to was that asymmetric.

Also for reference, most TCP stacks default to sending one ACK per two packets received.

But ACK aren’t the only upstream traffic. Latency gets added to all your requests.

What are you trying to say? What latency is being added to what requests? Are you arguing for or against ACK prioritization?

I am neither arguing for or against, just that delayed ACK probably isn't the only reason for the connection to become sluggish. A typical page makes dozens of requests, these are packets to be uploaded, if the uplink is saturated, the latency should increase, I'd expect that to affect the time it takes to render the page.

Backblaze has a bandwidth limit setting if this is a concern.

Yes - your first upload is going to be painful, but for the average user the following incremental backups are just a blip.

And if you're a business and have lots of files to backup, well, it's leased line time.

Took me the entire 15 day trial period for my initial backup of ~4TB. After that though, I never notice it uploading the incremental backups.

> Except that if you saturate your uplink you will also likely make your downlink sluggish.

That's why I said "half". And if you make 1TB per month then it's only 10%. You could restrict it to overnight too.

> And a user may not want to wait 20 hours for an operation to complete.

Maybe. Tape backups are often on a daily basis anyway.

Is this normal for Windows? I assume you are talking about Windows. Maybe it depends on the quality of your network stack?

I've been maxing out my uplink 24/7 for the last 10 years. My upload speed has increased from 15 KB/s to 100 Mb/s in that time, and for the life of me I could not feel or measure any difference in downlink speed or perceived performance after switching to about 1 Mb/s and up.

and after 1TB your ISP will charge you extra or claim you're "probably doing shady things" and disconnect you.

Prior to Backblaze, I used another service that shipped me a hard drive for the initial seed. 1 TB is painfully slow on my 100/5 connection.

Unfortunately they stopped all home sales, so it took weeks to seed to Backblaze.

Google and AT&T are taking their sweet-assed time laying fiber in my area, if they ever finish at all. 1G/1G is really the only solution.

If I'm not mistaken, Google has called off any plans for expanding Google Fiber.

https://arstechnica.com/information-technology/2016/10/googl...

They claim to have not stopped in KC, but in my area, the city has lengthened right-of-way permits out to 2025. Those were typically only issued for 1 year.

http://overlandpark.maps.arcgis.com/apps/Viewer/index.html?a...

> ~30mbit up cable

If you think this is bad, I recommend you stay 100' away from Canada at all times.

Some of us are lucky enough to live in cities with the foresight to install municipal fiber networks. I have 1Gbps symmetrical at home, which makes backup to the cloud very feasible.

A lot of people live in those cities (in my case, the publicly owned electric co). Then they sold it all off to Rogers. Anyone want 100/100 for $800/month?

Perhaps Elon's Starlink will save you at some point. (being serious here, the network should be able to support much better than cable.

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