I'm using CGWatcher 1.1.2 with cgminer 2.11.4 and I noticed that alot of my work is being thrown away. I have about 2x as many "Discarded" as "Accepted". I assume the discards are caused by the GPU not getting the work done fast enough before the server moves to the next block.
Here are some details:
Video Card: Radeon HD 7850 DD
Hash Rate(Litecoin) : 363 Kh/s
Accepted...............1377
Rejected...............91
Hardware Errors........0
Stale...0
Discarded...2382
worksize: 256
thread concurrency:8192
intensity:15-17 depending on desktop usage
Efficiency: 115%
Utility(shares/min):2.53
Mining Statistics:
Mining duration............... 9 hrs, 12 min, 55 sec
Current accepted work rate.... 0.042/sec (2.530/min)
Current discarded work rate... 0.073/sec (4.359/min)
Current rejected work rate.... 0.003/sec (0.166/min)
Current stale work rate....... 0.000/sec (0.000/min)
Network statistics:
Times Sent.................... 1,495
Bytes Sent.................... 169,526
Times Received................ 2,702
Bytes Received................ 830,288
Net Bytes Sent................ 169,526
Net Bytes Received............ 830,288
I've tried a couple different pools, but still high discards.
Is this normal? Is there any way to minimize the number of discards? Would worksize make a difference? Is it a network latency issue? Anything suggestions for what I can tweak to improve this would be appreciated.
Edit Update: I switched to another pool and discard rate has dropped from 200% down to 60%, so I think a large part of the problem was the pool.
Edit Update 2: Saw over in the cgminer thread that discards are "meaningless" which is why it was removed from the cgminer screen. So I guess there isn't anything that can be done about it. I think its related to hash rate - seems the lower the hash the more discards. This would make sense because the miner can't keep up with the pool. The pool moves on to a new block while the miner is still working on the old one, so the work gets tossed, if I understand things correctly.