I just tried again with the latest version from your github. I'm still seeing a drop in performance compared to the vanilla source.
My system went from ~7100 to ~4200.
This particular system has dual Intel Xeon Quad-Core CPUs (E5335) @ 2.00GHz.
Topic: 4 hashes parallel on SSE2 CPUs for 0.3.6 - page 2. (Read 22054 times)
I can confirm that the patch now works just fine. I just generated my first 50 BTC with it. And since this patch doubles the speed I think it's only fair if I donated half of that to tcatm.
That's nice to hear. Thanks for the donation and thanks to everyone else who donated!
I can confirm that the patch now works just fine. I just generated my first 50 BTC with it. And since this patch doubles the speed I think it's only fair if I donated half of that to tcatm.
CRITICAL_BLOCK is a macro that contains a for loop. The assertion failure indicates that break has been called inside the body of the loop. The only break statement in this block is in line 2762. In the original source file, there is no break statement in this critical block. I think you must remove lines 2759-2762. The is nothing like that in the original main.cpp.
Sorry about that. CRITICAL_BLOCK isn't perfect. You have to be careful not to break or continue out of it. There's an assert that catches and warns about break. I can be criticized for using it, but the syntax would be so much more bloated and error prone without it.Is there a chance the SSE2 code is slow on Intel because of some quirk that could be worked around? For instance, if something works but is slow if it's not aligned, or thrashing the cache, or one type of instruction that's really slow? I'm not sure how available it is, but I think Intel used to have a profiler for profiling on a per instruction level. I guess if tcatm doesn't have a system with the slow processor to test with, there's not much hope. But it would be really nice if this was working on most CPUs.
Thanks! That got probably mixed up when I patched the file with an older diff. I fixed the git: http://github.com/tcatm/bitcoin-cruncher
CRITICAL_BLOCK is a macro that contains a for loop. The assertion failure indicates that break has been called inside the body of the loop. The only break statement in this block is in line 2762. In the original source file, there is no break statement in this critical block. I think you must remove lines 2759-2762. The is nothing like that in the original main.cpp.
Oh, that's a part in the code my patch doesn't touch. You could try to remove line 2741 (CRITICAL_BLOCK(cs_main)).
Here's the output on stderr:
Code:
bitcoind: main.cpp:2741: void BitcoinMiner(): Assertion `("break caught by CRITICAL_BLOCK!", !fcriticalblockonce)' failed.
Yes, test is single threaded. Is there any output on stderr? From the coredumps I can tell that there must be some output.
The problem seems to be hard to debug, though. Is the khash/s you get worth it anymore at 352 difficulty? I'm only getting a block once a week now. If you want to keep the block chain working, you should use the original client. If you want to gain lots of bitcoins you should use a GPU.
The problem seems to be hard to debug, though. Is the khash/s you get worth it anymore at 352 difficulty? I'm only getting a block once a week now. If you want to keep the block chain working, you should use the original client. If you want to gain lots of bitcoins you should use a GPU.
The test program does not fail
Finally, I have the same problem with both -march=amdfam10 and -march=native. The cpu is a Opteron 2374.
Code:
$ ./test ../blocks.txt
SHA256 test started
70293
found solutions = 70293
total hashes = 139463136
total time = 63250 ms
average speed: 2204 khash/s
Does the test program run on a single thread?SHA256 test started
70293
found solutions = 70293
total hashes = 139463136
total time = 63250 ms
average speed: 2204 khash/s
Finally, I have the same problem with both -march=amdfam10 and -march=native. The cpu is a Opteron 2374.
That's not a real crash this time. It's an assert that fails in the miner. Most likely assert(hash == pblock->GetHash());. Can you run the test programm (explained in https://bitcointalksearch.org/topic/m.7096 If it fails, can you change -march=amdfam10 back to -march=native in makefile.unix, rm cryptopp/obj/*.o and recompile everything? What cpu are you running it on?
Ok I tried again, this time with no extra patches. I just cloned your git tree and compiled it. It still crashes. Here's the stack backtrace:
here (link removed) the sources with the object files as well as the a core dump and the binary.
Code:
#0 0x00007ffff710b1b5 in raise () from /lib/libc.so.6
#1 0x00007ffff710c5e0 in abort () from /lib/libc.so.6
#2 0x00007ffff71042d1 in __assert_fail () from /lib/libc.so.6
#3 0x00000000004628de in BitcoinMiner () at main.cpp:2741
#4 0x0000000000462d70 in ThreadBitcoinMiner (parg=0x391e) at main.cpp:2518
#5 0x00007ffff6ec3894 in start_thread () from /lib/libpthread.so.0
#6 0x00007ffff71aa07d in clone () from /lib/libc.so.6
I have also uploaded #1 0x00007ffff710c5e0 in abort () from /lib/libc.so.6
#2 0x00007ffff71042d1 in __assert_fail () from /lib/libc.so.6
#3 0x00000000004628de in BitcoinMiner () at main.cpp:2741
#4 0x0000000000462d70 in ThreadBitcoinMiner (parg=0x391e) at main.cpp:2518
#5 0x00007ffff6ec3894 in start_thread () from /lib/libpthread.so.0
#6 0x00007ffff71aa07d in clone () from /lib/libc.so.6
I had 5 machines running today and when I checked back 10 hours later, 4 of them had crashed, in the same way as with the previous times (i.e. right after they had generated a new block but before they broadcasted it).
I created a tarball containing the coredump, backtrace, binary and the sources I used to compile it including the compiled object files. You can get it fromhere (link removed). Hope that helps.
EDIT: Ok, I just noticed that both your patch and the patch for the getkhps rpc (from http://www.alloscomp.com/bitcoin/) modify the function BitcoinMiner in main.cpp (which is where the segfault occurs) so this must be the reason for the seqfaults. I will try to test it without the getkhps patch.
I created a tarball containing the coredump, backtrace, binary and the sources I used to compile it including the compiled object files. You can get it from
Oh thats easy: Get two nodes on a seperate network and connect them using -connect=other_nodes_ip and a seperate/empty datadir.
Just a comment that this would be easier to test if difficulty were set to '1' in the client.
GDB can also generate coredumps with the command generate-core-file. It might be useful to reconstruct the cause for the segfault. Please note, that the coredump might include your wallet so it's probably a good idea to run bitcoind on a seperate datadir.
I modified bitcoind so that it doen't fork to the background and now I can debug it with gdb. Next time it crashes gdb will give me a backtrace.
Did your kernel write a coredump and if so can you mail me the binary + coredump to [email protected]?
I did segfault according to dmesg:
I don't have a stack trace.
Code:
bitcoind[2469]: segfault at 0 ip 00007fe92c5b3f32 sp 00007fff15e5f6b0 error 4 in libc-2.11.2.so[7fe92c57e000+150000]
I don't have a stack trace.
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