Bufferbloat is not necessarily bad, probably easier to manage via shaping, than if an isp has tiny buffers and chooses to drop packets instead.

Delayed packets are also a lesser evil vs dropped packets.

I found on DSL with my tests on UDP iperf, anything above about 20% utilisation I started getting dropped packets, it hit a level which would be real world affecting at only about 60% utilisation.

Whilst on 4G and cable, where buffer bloat seems more of a thing, the packets dont get dropped until almost 100% utilisation, which to me is much more preferable behaviour. Granted on gigabit cable the sheer size of the pipe helps, but 4g is still under 200mbit, and doesnt have the DSL packet loss problems I had. I prefer my ISP to keep the packets in transit rather than dropping if is local congestion and to manage the congestion myself.

Edited by Chrysalis (Tue 10-Jan-23 15:47:11)

Random thought …. your HG612, have you tried replacing it ? It is VERY old tech now.

There's not really anything better, depending on your line. If it was failing I'd expect lockups/sync drops rather than bloat.

The ECI tended to have caps go bad, the HG612 seems better built.

In reply to a post by Zarjaz:

Random thought …. your HG612, have you tried replacing it ? It is VERY old tech now.

Old tech or not, Why would i have the issues SINCE a Topology migration? Can you tell me how this " old tech," that may not be as used as you think it maybe ,is the culprit?
IMO change of backhaul provider is the problem, I bet i could arrange for a loan router /modem that zen supply and the buffer bloat when downloading multithreaded would be the same or similar , SIMILAR BECAUSE THEIR SUPPLIED CPE IS 1 GB MODEM The HG612 is only 100mb as is the EWAN on my Billion router , but has 1gb lan

and i have found that if i pause a download and start another straight away the buffer bloat is reduced to below the average of 60 ms , but start to download a new file and it returns up has high as +400 ms my upstream used to be the biggest buffer bloater, typically over 100ms, multithreaded ftp now that is around 60ms Me thinks config issue ZENS side

Edited by tommy45 (Thu 12-Jan-23 21:48:22)

Have you had a chat with technical support and are you actually noticing anything that is impeding what you are trying to do with your connection?

You can have too much information, if it's not causing you a problem, why worry?

If it is preventing you from doing something, ring them and have a calm chat, always found them more than willing to run tests and to help you narrow things down, one of the reasons I've been a customer for so long.

I have been in contact with support and after explaining a few times what the issue was Excessive buffer bloat whilst downloading , They set up monitoring of the latency but their graph didn't really show the detail needed , so i sent them snapshots of my tbqm and f8lure graphs and they agreed this was not normal,

so to rule out my equipment, they asked if i would mind if they sent me a fritzbox to rule this out , i set up the new router and tested to see if it had resolved the issue, which It had, so out of curiosity i swapped back to my old set up, and the problem did not re-occur, to the cause ???? maybe some kind of glitch with the DSLAM /line card or the modem that cleared as a result of connecting to a different modem ?

And the old hardware had had several re synchs following the network migration in April ,although it had increased since then , as a result i lost the full synch and 5db snr i obtained following a re-synch following a brief (under 30sec) power outage, But buffer bloat back to normal ,infact a slight improvement on upstream buffer bloat when several FTP threads are active

Edited by tommy45 (Wed 18-Jan-23 23:13:18)