Some quick mining benchmarks:
On a machinewith 2 x Xeon E5620, 16 threads. Same .bat for each.
Testz compiled v1.1 : 80 Kh/s
DeMarcus v0921 generic : 89 Kh/s
Spexx : 42 Hh/s
Something weird is happening with Spexx's version. If I run another instance simultaneously it picks up to a combined total of ~70 Kh/s.
The weird behavior you noticed was discovered in an earlier version compiled by somebody else. The problem arises when using --threads greater than 1 and you can see what is going on by using the Windows Task Manager (and Process Explorer if you are a proper geek
). Try starting 16 instances of minerd with --threads 1 and you should see an immediate significant improvement. I found that a small further improvement was obtained by forcing each instance to use a predetermined set of three cores, balancing the load. To do this, create a batch file with startup commands thus:-
start /low /min /affinity 0x7 minerd etc
start /low /min /affinity 0xb minerd etc
start /low /min /affinity 0xd minerd etc
start /low /min /affinity 0xe minerd etc
start /low /min /affinity 0x70 minerd etc
start /low /min /affinity 0xb0 minerd etc
start /low /min /affinity 0xd0 minerd etc
start /low /min /affinity 0xe0 minerd etc
start /low /min /affinity 0x700 minerd etc
start /low /min /affinity 0xb00 minerd etc
start /low /min /affinity 0xd00 minerd etc
start /low /min /affinity 0xe00 minerd etc
start /low /min /affinity 0x7000 minerd etc
start /low /min /affinity 0xb000 minerd etc
start /low /min /affinity 0xd000 minerd etc
start /low /min /affinity 0xe000 minerd etc
I found with further testing that it was possible to wring a tiny bit more performance out by having each process/thread connect to a unique worker profile on the pool(s) and the method above will also allow simultaneous connection to more than one pool. I have a quad-core processor with four minerd processes running thus:-
start /low /min /affinity 0x7 minerd --url stratum+tcp::/xmg.suprnova.cc:7127 --user Spexx.Spexx --pass stratocaster --threads 1 --quiet
start /low /min /affinity 0xb minerd --url stratum+tcp::/xmg.suprnova.cc:7127 --user Spexx.Spexx1 --pass stratocaster --threads 1 --quiet
start /low /min /affinity 0xd minerd --url stratum+tcp://mine2.magi.nonce-pool.com:4090 --user Spexx.Spexx --pass stratocaster --threads 1 --quiet
start /low /min /affinity 0xe minerd --url stratum+tcp://mine2.magi.nonce-pool.com:4090 --user Spexx.Spexx1 --pass stratocaster --threads 1 --quiet
This should help a great deal. I would be very interested to see a revised set of results from your machine when using this balanced startup regime with the various versions of minerd now available.