Troubleshooting tips before I cancel? Fusion has degraded rather badly for me after many years of generally good speeds

[pelleas]

I have base Fusion account which I've happily used for years. I've been an ombudsperson for Sonic service in general, and have recommended Sonic to several friends who now use the same Fusion service.

However, while such a friend on my same block (and therefore about the same distance from the nearest switch) is getting 20+ Mbp/s download and ~3 up, over the past months sustained uploads (all via FTP) have become a huge problem for me, bringing the connection to its knees.

When I monitor the FTP transfer from both ends I see the upload in real terms is < 1440 dial up.

Sonic support has maintained that upload saturation can cause download performance to be unusable (my word, not theirs). By 'unusable', I mean ping times of ~900ms, ~30 seconds to send a text email, et cetera.

In my previous experience, FTP uploads limited download speeds a bit but generally were around 1Mbp/s, which is consistent with Fusion spec.

I'm only getting a tiny fraction of that speed as measured by the download rate from the other end of the FTP connection.

Is there something I'm missing here? Sonic support hasn't suggested any internal checks on my side; they see the connection syncing at 7 down and 1 up even though I'm getting just a fraction of that.

[m.harmon]

The best bet is to give us a call when you have a chance. I am seeing your upload being maxed out almost all the time and to better narrow down if that is the issue or its somewhere else we would want to do some real time troubleshooting. Email is great for some things but to solve the issue we would want to be looking at your circuit at the same exact time you are.

[pelleas@sonic.net]

Being online together at the same time isn't necessary to answer the question I posted -- in fact, it obscures the question.

e.g.:

How and why would a normal FTP upload saturate a Fusion connection while the other end of the FTP is downloading at ~dialup speeds?

If all uploads saturated a Fusion connection, users would notice all the time.

Is there any other line diagnostics or reason for this new behavior?

[amayfield]

FTP (File Transfer Protocol) is a client-server model which means a client uploads a file to a server and then another client can download that file from the server. This means with FTP you are not uploading directly to someones computer (unless their computer is the server), so there can be (and likely will be) disparity between the upload and download speeds.

In your specific case you are uploading at your maximum available bandwidth, presumably during these FTP transfers, which means there is no available upload bandwidth for other devices to utilize (to browse the internet for instance). A good way to avoid these kinds of situations is to limit the upload bandwidth available to the the FTP program to about 75% of your maximum upload bandwidth (which would be to limit it to about 750 Kilobits per second).

In terms of explaining the new behavior - looking at the historical bandwidth usage graphs for your account there has been a steady upload at maximum bandwidth rate for the past couple of weeks - which is a significant increase in usage in comparison to previous weeks and months. Have you been uploading larger files to your FTP? That may account for the increased upload bandwidth usage as larger files will take longer to upload.

[pelleas@sonic.net]

Thanks @amayfield,

To be clear, my linux server at home is receiving the SFTP handshake from a remote computer, so it's really two computers without the mediated server in the cloud you assumed when I mentioned FTP.

I'm initiating both sides of the transfer between both computers via shells.

My upload is saturated to the point of desperation, but the download as seen from the remote system connected via SFTP is 0.1-0.2 Mbp/s. As I wrote, that's what's surprising.

If I was getting anything close to 1Mbp/s the transfers would be mercifully short and any download interruptions from saturation therefore mostly inconsequential.

But because the transfer is so slow, uploading/downloading even small files via SFTP is taking a long time and the download bandwidth is hopeless during all that time.

You may wonder if it's bandwidth limited on the SFTP client, but I've tried transfers from near (San Francisco, 10 miles away) and far (Paris, ~9,000 miles away) and the download speed is the same -- around 14.4 dialup in fact.

I would be willing to try the Sonic fiber+copper service but my suspicion is that if I'm not getting close to 1Mbp/s with Fusion, I may not get an appreciable improvement with a new service since 5x dialup is still pretty slow for 2017.

Thanks again, I'm all ears for your suggestions, including any line problem potentials on my side although I've changed no wiring in the last year.

[dherr]

I am not clear if Sonic is saying that your upload has been only saturated during your FTP sessions or if it is saturated 24x7. If the later then it sounds like you might have a compromised host or some other diagnosed issue that is complicating this.

It might be worth trying a base level test of:

1. turn off wifi at the router.
2. test download and upload speed from a single wired host with nothing else plugged in.
3. if that looks good then slowly start to bring up other clients.

You may have already done all this, but wanted to add the suggestion just in case, since it does not look like there is a clear resolution to your issue.

[pelleas@sonic.net]

Good suggestion @dherr -- I did try a single wired connection when I first noticed the download lag, and saw the same thing.

I'll try again for a fresh test, but I'm doing another large upload which I want to complete first.

In the mean time, I throttled the SFTP transfer rate to 85KB/s, leaving a bit of headroom as 125KB/s is the best-case upload for my Fusion based on past tests.

I haven't seen any change in the download speeds with the new headroom; upload seems to be saturating in the same way but perhaps the Sonic techs can monitor and see something changed on their side.