Slow hashing XMR with 2 x Opteron 6376

[boumacor]

For the last couple of days I have been trying to hash some XMR with a Proliant DL385p Gen8 server (32 GB Ram) with 2 x Opteron 6376 (so 32 Cores in total ). After the installation of Ubuntu 16.04 and updating the software I've installed a couple of linux miners but the all seem the have the same result. Hashing should be around 1561 H/s (http://monerobenchmarks.info/searchCPU.php) but on my system it's just 930 H/s. I've tryed XMRig, xmr-stak, xmr-stak-cpu, sgminer, cpuminer-multi and a couple more.

So now I'm wondering, am I doing something wrong ? Or are the numbers on monerobenchmarks wrong. If i'm checking this link ==> https://www.reddit.com/r/MoneroMining/comments/6ljys6/need_help_with_dual_amd_opteron_6276/ This a dual 16 Core AMD CPU with around 1000 H/s. The 6276 has a clock of 2,3 Ghz (2,6 Ghz turbo), the 6376 has the same CPU speeds, so perhaps 930 H/s is the max ? When using the 6276 CPU at monerobenchmarks the numbers are closer to mine (between 970 H/s and 1003 H/s)

Any thoughts ?

[1714017926]

1714017926

[1714017926]

1714017926

[1714017926]

1714017926

[1714017926]

1714017926

[1714017926]

1714017926

[Branko]

Don't use more than 8 cores per CPU if info I found on net about size of L3 cache (16MB) is correct

[boumacor]

According to iLo the numbers are :

Internal L1 cache   768 KB
Internal L2 cache   16384 KB
Internal L3 cache   16384 KB

And you're right, maximizing the amount of cores to 16 the performance is optimal. So perhaps use a different algo ? Any idea's ? What will work for this server ?

[Branko]

I don't think you have much options for cpu mining, if any beside cryptonight

[spinx]

Each miner thread needs 2Mb of L3 cpu cache.

On my rig, I have 4x E7-8837 cpu's, which are 8 cores each, no hypherthreading, so 32 physical cores total.
Each cpu has 24Mb cache, so 24Mb/2Mb=12 threads for mining on each cpu.
To get 12 total threads running on the 8 cores, I run two threads on 4 of the cores, and one thread each on the other 4 cores = 8 total cores of the cpu..
To run two threads I set 'low_power_mode=true', and to run one thread I set 'low_power_mode=false'.
So for each cpu, this is what I do on my E7-8837:

{ "low_power_mode" : true, "no_prefetch" : true, "affine_to_cpu" : 0 },
{ "low_power_mode" : true, "no_prefetch" : true, "affine_to_cpu" : 1 },
{ "low_power_mode" : true, "no_prefetch" : true, "affine_to_cpu" : 2 },
{ "low_power_mode" : true, "no_prefetch" : true, "affine_to_cpu" : 3 },
{ "low_power_mode" : false, "no_prefetch" : true, "affine_to_cpu" : 4 },
{ "low_power_mode" : false, "no_prefetch" : true, "affine_to_cpu" : 5 },
{ "low_power_mode" : false, "no_prefetch" : true, "affine_to_cpu" : 6 },
{ "low_power_mode" : false, "no_prefetch" : true, "affine_to_cpu" : 7 },

Then I duplicate that configuration four times for the other 4 cores.

This is also the suggested configuration from xmr-stak-cpu.

[greyday]

You will get twice as many threads mining crytponight light coins (1MB per thread instead of 2MB), though I can't speak to the value/earnings. I think AEON is one?

[boumacor]

Good thinking, I'll look into crytponight light

Thanks

[mohammadadam]

HI, i too have a dual opteron 6376. My maximum hashes are the same as yours. Did you find a solution for this yet. What are you mining now?, any help is appreciated

[ronnylov]

I Think you can expect around 1000 H/s with two Opteron 6376. I have four Opteron 6276 and can get at max 2000 H/s and the 6376 is about same performance but with lower power consumption.

[mohammadadam]

Thank you for the reply, can you share the details of your config file and on which miner are you mining. Also as the op posted the monero benchmarks is not true then.

[ronnylov]

You can check this thread regarding config
https://bitcointalk.org/index.php?topic=1809877.0

Edit: Regarding the monerobenchmarks it may have been an overclocked system. Who knows it is just one entry made by some random person. I read somewhere about overclocking of these CPU's up to 4 GHz with water cooling and motherboards with modded bios but also Power consumption of 1000 W... Not Worth doing for mining.

[mohammadadam]

Thank you for the info, but my miner is giving lesser hashes with this config. Also the L2/L3 cache is erroneously shown as 64/24 in xmrig. Is there any way i can change this?, Are you to experiencing same issues, as in error in cache memory?

[Pyrojason]

bump - Instead of starting a new thread  - Did you figure out why it was hashing so slowly?

[martychubbs]

Well, my first idea was about installation process itself, kind of, was it ok?
and are you sure about that? then, there's probably something about the number of cores.
if it's in excess then troubles may occur. and by the way, what are you mining? jut to get a clear picture.
I just had a thought that power consumption somehow can affect the process of hashing as well.

[serhanni]

bump - Instead of starting a new thread  - Did you figure out why it was hashing so slowly?

You can also ask on servethehome forums. They are using their servers to mine monero.

[Pyrojason]

bump - Instead of starting a new thread  - Did you figure out why it was hashing so slowly?

You can also ask on servethehome forums. They are using their servers to mine monero.

Thanks - might check it out.