acceptable error seconds limit

hi people, was just wondering from the many learned people on here what a reasonable amount of error seconds per day
Reason im asking is ive just decided to try my line without interleaving on to get better pings, with interleaving was averaging about 150 es per 24hr period.
Nowthat i am on fast path as of yesterday this has shot up, which i expected, but what i was wondering is what amount would be classed as a problem to my line
ie- first day of fast path yesterday- 1600 es
today i have had 700, although i used dmt tool to connect at a higher snr
also yesterday i had 2 disconnections in evening and today had none,
I would prefer the better pings, 20ms to jolt on fast path, 40 interleaved, but stability of the line is quite important as well.
im about 3km from exchange, and sync at approx 5500, get a 4.5mb line from this, snr is about 6, but currently running it at 9, have 46db downstream attenuation
any help or thoughts please on whether my line is gonna be ok for fast path or not, gonna monitor it through the week but it would be nice to have some guidelines of what is good and bad

The final arbiter is whether or not the line is still usable for browsing etc. and whether or not the download throughput is better or worse than it was before.

I had to have interleave applied - without it the error rate over short periods was so high that sites were timing out. It isn't possible to give an acceptable number over a day because they won't be spread out - they'll come in clumps.

I agree it would be be useful to know what BT see as normal and where the amount of errors recorded will break a threshold.

That sounds like quite a lot or Error Seconds to me. I only see Error Seconds when the line is really bad - lately when there is a storm around.

Even though my line is fairly noisy with sometimes a few 1000 CRC/HECs in a day and often 1/2 million FECs(I'm Interleaved), it always worries me if I see any Error Seconds.

I think I would be concerned that BT will raise your target SNR if the errors continue.

Unless I'm wrong the only thing that will get your margin increased is frequent forced resyncs. Unless the DSLAM is inspecting the traffic so it knows which packets are retransmits or querying your router (both of which I seriously doubt) it isn't going to have any idea at all whether or not the packet got through OK.

Not sure about that...

I recently had my SNR put back from 9 to 6dB. Although the connection was rock solid and didn't resync once, my Target SNR went back to 9 after a couple of days. The only thing that I think it could be is the number of errors.

John.

Maybe but I've had the opposite experience. Huge numbers of errors and no change in target. I even had to ask for interleave to be applied manually. OTOH I do know that resyncs get your target raised - I started out on Max with the abysmal Draytek 2600 and my target was up to 12dB by the time I realised it was useless and replaced it.

I wish my SNR had stayed down. It was only when I swapped router that I realized that my target SNR had been raised. I finally got a reasonably steady snr trace to I could see it!

It could well be that, when BT dropped it back to 6dB, it didn't "stick" for some reason (maybe the engineer forgot to hit the Save button!). Whatever the reason, my ISP says I now have virtually no chance of getting BT to do it again.

My current stats on 9dB after 160 (WAN) hours are:

SF: 33995799
SF Errors: 2592
Reed Solomon: 2311714378
RS Corrected: 33924126
RS Un-Corrected: 27569
HEC: 2331
Errored Seconds: 4449
Severe ES: 49
Interleave Depth: 16

Unfortunately, I wasn't on 6dB long enough to get around to noting the errors!

John.

I'm not sure how useful 'errored seconds' really is.

I've seen it defined as 'the number of seconds in which at least one error occurred'. One errored second could contain a single error or thousands of errors.

A line with a hundred errored seconds during one hour could be perfectly acceptable if each second only had one error. On the other hand a line with ten errored seconds could be awful if every second contained thousands of errors.

...and there of course is another one which some routers report "Severe ES: 49". Without some definition of what that means it probably isn't a lot of use but I'd take it to mean that there were so many errors in the second that very little data actually made it unscathed.

i definitely seem to get more errors on a lower snr settting, on 6 it was 1600 a day, yesterday i used dmt tool to increase snr to 9 and i got half of that, to test it out again ive let the normal snr happen today and ive got 1100 error seconds with 4hr of day left, had 1 d/c today and none yesterday with the higher snr.
I may just have to accept a slightly lower speed on line if im gonna stay on fast path,
1/2 mb drop vs good pings hmmmmm