Throughput as a % of sync speed

[ianm1309]

Hi

Just a quick query relating to throughput as a percentage of sync speed.

This was discussed back in Aug 2017, but more in relation the rollout of reduced SNRM.

I have an unlocked HG612 front ending a HH5, and the hub reboots every 14 days, like many others.

My percentage value has always been around 90% of sync, but very occasionally, following a HH5 reboot, it has lowered to 85%. I've always been able to fix this by manually rebooting just the HH5.

I've just renewed my contract, and sync speeds were unaffected. However, a couple of days later the HH5 rebooted  (outside its usual 14 day cycle) and my percentage went down. Rebooting the HH5 won't budge it back up this time.

So stats are: before latest reboot - downstream sync  = 48820kbps, speedtest  = 43773kbps (ie 89.6% of sync speed).  After latest reboot - downstream sync = 48820kbps, speedtest = 41417kbps (ie 84.8% of sync speed).

Now, obviously this isn't a show stopper, and I'm happy with the speeds I'm getting, but does anyone (expert) have any idea why the percentage throughput varies and can (usually) be corrected simply by rebooting the hub?

Dslstats report:

Stats recorded 05 May 2019 14:20:16

DSLAM/MSAN type:           BDCM:0xb12d / v0xb12d

Modem/router firmware:     AnnexA version - A2pv6C038m.d24j

DSL mode:                  VDSL2 Profile 17a

Status:                    Showtime

Uptime:                    273 days 14 hours 14 min 41 sec

Resyncs:                   0 (since 05 May 2019 09:36:12)

                          Downstream Upstream

Line attenuation (dB):     20.7       0.0

Signal attenuation (dB):   Not monitored       

Connection speed (kbps):   48820      7682

SNR margin (dB):           3.7        5.8

Power (dBm):               13.0       3.6

Interleave depth:          4          1

INP:                       54.00      0

G.INP:                     Enabled    Not enabled

Vectoring status:          5 (VECT_UNCONFIGURED)     

RSCorr/RS (%):             20.3579    1.3377

RSUnCorr/RS (%):           0.0000     0.0000

ES/hour:                   0          12.2

Any thoughts welcome.

[imjolly]

run btspeedtester and after first test run diagnostic test and post results  there is no fixed perdectage between connection and download/thoughput speed and on fixed percentage is between conenction speed and ip profile  your download speed should always be less than ip profile which allows for overheads   http://www.speedtest.btwholesale.com/

[DiggerOfTrenches]

The 15.87 you are measuring needs to divided by 0.882 to compare it accurately 15.87/0.882 = 17.99Mb which is the 17990 sync/data rate speed you are seeing.

As your hand back lowest threshold is 11.4Mb. You would have to have a speed test of 11.4*0.882 = 10.05Mb to hand back.

If it is 14.4 = aprx 12.70. If you have been given a different guarantee you can calculate the true value now.

Does this help? x0.882 or /0.882

[imjolly]

@DiggerOfTrenches 

are you sure you posted on correct thread as speed on router is 48820kbps not 17990kbps

[ianm1309]

@imjolly   Thanks for your reply. Here are the results.

[DiggerOfTrenches]

No too lazy to edit my cut and paste job.

The maths is the important bit.

@ianm1309  will work it out.

[DiggerOfTrenches]

08:52:44, 19 Oct.

(493999.520000) PPPoE is up -​ Down Rate=47948Kbps, Up Rate=5297Kbps; SNR Margin Down=6.1dB, Up=6.3dB

Look for something like this in your HH5 log.

[pippincp]

---

@DiggerOfTrenches wrote:

08:52:44, 19 Oct.

(493999.520000) PPPoE is up -​ Down Rate=47948Kbps, Up Rate=5297Kbps; SNR Margin Down=6.1dB, Up=6.3dB

Look for something like this in your HH5 log.

---

Those figures are held by the modem not the HH5 acting as router only.

[DiggerOfTrenches]

Having read and now understood your OP.

Answer = 88.2%

What is minimum speed stated in your new contract(e-mail)?

[ianm1309]

Hi

Mimimum speed is stated as 32Mb, so I've no problems there.

Looks like profile is set at 88.1% of sync speed and BTW download speed shows 96.7% of profile, so no compaints there either.

I can only conclude that my profile was lowered slightly by re-contracting. Not sure why, since I was assured this was only a billing exercise.

Anyway, going back to my OP, it's interesting that, after an unscheduled (ie not 14 days) hub restart when my download speed vs sync speed was lowered, I could always get the speed back by simply restarting the hub (modem untouched). I never checked my profile on these occasions so I can't confirm whether this ever changed.

Guess I'll wait and see if anything changes in the coming days/weeks.