21% Rejected shares normal? (0 HW)

Hey everyone, I’m new to mining and just started out on FTC. I am using cgminer 3.3.1 with CGWatcher. Right now, it is reporting about 21% of my shares are rejected. Is this normal or do I need to optimize this to bring it down? Right now I am mining on wemineftc.com (started there with LTC for a short while and then switched to FTC). Here is what my setup looks like.

i7-2600k
16GB memory
PowerColor 6970 940MHz/1425MHz w/ 12.8 drivers

On wemineftc.com (VARDIFF), my current diff is 56 with a suggested 96 and max 192.

cgminer.conf:
“intensity” : “13”, (I have CGWatcher increase this to 18 during inactivity)
“vectors” : “1”,
“worksize” : “256”,
“lookup-gap” : “0”,
“thread-concurrency” : “8000”,
“shaders” : “1536”,
“gpu-engine” : “0-0”,
“gpu-fan” : “auto”,
“gpu-memclock” : “0”,
“gpu-memdiff” : “0”,
“gpu-powertune” : “0”,
“gpu-vddc” : “0.000”,
“temp-cutoff” : “90”,
“temp-overheat” : “85”,
“temp-target” : “75”,
“api-port” : “4028”,
“expiry” : “120”,
“gpu-dyninterval” : “7”,
“gpu-platform” : “0”,
“gpu-threads” : “2”,
“hotplug” : “5”,
“log” : “5”,
“no-pool-disable” : true,
“queue” : “1”,
“scan-time” : “30”,
“scrypt” : true,
“temp-hysteresis” : “3”,
“shares” : “0”,
“kernel-path” : “/usr/local/bin”
}

from CGWatcher:
Accepted… 12360
Rejected… 3323
Hardware errors… 0
Utility… 5.31
Diff1 work… 1014071
Accepted difficulty… 823944
Rejected difficulty… 188432
Last share pool… 0
Last share time… 1374346207
Last share difficulty… 56
Last valid work… 1374346207
Driver… opencl
Kernel… scrypt
Codename… Cayman
Device path…
Identifier… /atigpu/0
Device… 0
Bus… 1
OpenCL Device ID… 524041280
Temp-target… 75Â°C
Temp-overheat… 85Â°C
Temp-cutoff… 90Â°C
Overheat Protection… CGWatcher
Overheat count… 0
Cutoff count… 0
Last well… 0 sec ago
Last not well… 18 hrs, 50 min, 15 sec ago
Reason not well… None
No-start count… 0
Comms error count… 0

svennand

21% is VERY high, i usually are not satisfied until im at under 1.5% with overclocked settings

Try running the card at stock speeds (880/1375), and thread-concurrency to 8192 (the number that most have the best result with) and se what happens to the rejected.
Also try another pool, might be that the timing between your connection and the pool is off. recommend you try ftc.nut2pool.com which has really low latency connection!
No adverticing, but try it for the testing part. it works like a charm for me if you look at my stats: http://50.87.190.116/monitoring/

btw do you still have so much rejected? can it have been during the attack at feathercoin (lots off orphan, maybe there was some ddos that made you lose connection in between).

I earlier had 7x 6970 and no one of them gave me any trouble, had around 450khash each at stock settings. no hw error and very low reject/stale.

I checked and I had about 7 more rejects than when I posted the original message about 4 hours ago, so its possible that most of them came from the attack.

I tried 8192 concurrency again and it caused my hash rate to plummet as I remembered when I set it up. With 8192 I hash in the low 400s, at 8000 I’m over 500.

I should have noted in there that the 940/1425 clock rate is stock for my 6970, it was a factory overclocked card.

I’ll let it go for a while and see how the ratio stays, and then try another pool if it continues to be a problem. Thank you for confirming that it is definitely a problem!

EDIT: looked at your stats and that is just sick, nice work ;D

ghostlander

Set lookup gap to 2, thread concurrency to 8000, remove vectors and shaders.

Tuck Fheman

there is another (more probable) reason for the rejects (at the time he posted), considering we all experienced them.
[url=http://forum.feathercoin.com/index.php?topic=2866.msg22210#msg22210]
http://forum.feathercoin.com/index.php?topic=2866.msg22210#msg22210[/url]

svennand

[quote name=“Tuck Fheman” post=“22462” timestamp=“1374384735”]
there is another (more probable) reason for the rejects (at the time he posted), considering we all experienced them.
[url=http://forum.feathercoin.com/index.php?topic=2866.msg22210#msg22210]
http://forum.feathercoin.com/index.php?topic=2866.msg22210#msg22210[/url]
[/quote]

thats why i asked him if it still happens=)

After mining all night I’m getting 1.3% rejected, so it appears it was due to that attack. Thanks for the help!

svennand

[quote name=“jsteinm1” post=“22524” timestamp=“1374427330”]
After mining all night I’m getting 1.3% rejected, so it appears it was due to that attack. Thanks for the help!
[/quote]

Sweet!

Recommend you setup failover-only option to another pool.
That way if one pool goes down under ddos your miners will redirect their power.
However there was an exploit in statum protocol under this attack which gave the miners rejected shares. so i do not think failover would have saved you anyway during that attack :)

Wellenreiter

I’m still at 15% rejected. Will check tomrrow what I can do about that.

Have a micro rigg only, anyway. ;)

It’s one 6670 running at 130 khash…lol

svennand

[quote name=“Wellenreiter” post=“22530” timestamp=“1374429262”]
I’m still at 15% rejected. Will check tomrrow what I can do about that.

Have a micro rigg only, anyway. ;)

It’s one 6670 running at 130 khash…lol
[/quote]

restart the miner to zero out the stats. if you had it running the entire time the stratum exploit was going on it will take quite a bit of time to get low rejected % ;)

Wellenreiter

Found out, that it seems to be related to my setup.

I’m using bfgminer and when I set the intensity higher than 15 the number of rejects starts to increase.

As the output of the bfgminer is sent to the KDesktop, I assume the screen updates start to be delayed and cause a delay in sending data to the pool server as the miner process waits for the screen output to be completed and that this results in the rejects.

My system is not optimized for mining, has got only 2GB main mem and a 6670 with 1 Gb mem only. Therefore I think I have to live with the situation.

svennand

try cgminer and see if you get the same experience.
increasing intensity will yield in higher reject rate if you allready are
pushing the card. at least thats my experience

main memory size is overrated. im running 2gb on my 4x7970 rig. no difference at all from
when i had 4gb. get stable 3mhash