Segmentation fault


Just Got Here
I'm attempting to run a geometry optimization on a fluoride at the DFT level of theory using the B3LYP functional, ZORA, and ANO-RCC basis set. However I've arrived at the following error and can't for the life of me figure out what it's trying to tell me. The message is:

int_init: internal texas instability possible cando_txs set to always be F
Segmentation fault

Any ideas on how to address this are most appreciated.

Thanks in advance,
Tom

Clicked A Few Times
int_init:
Hello Tom,

its only a guess, but segmetation fault could mean that you have a problem with your memory. On Linux systems you can check your memory allocation out via this:
(its from a different qc-program, but the topic is the same)


any computer companies ship their operating systems with the parameters
for SYSV set to values too small to be useful. Chief among these is the
maximum number of bytes in a single shared memory region, usually called
with a name containing 'shmmax', but in some cases limits on the semaphores
also need to be raised. On our own computers, where we allow a single
GAMESS application to use all the physical memory of the computer, we
just set the 'shmmax' memory limit equal to the installed RAM.

A table of how many bytes might be contained in your memory is useful,
      384 MByte      402,653,184
512 MByte 536,870,912
1 GByte 1,073,741,824
1.5 GByte 1,610,612,736
2 GByte 2,147,483,648
4 GByte 4,294,967,296
8 GByte 8,589,934,592
16 GByte 17,179,869,184
24 GByte 25,769,803,776
32 GByte 34,359,738,368
48 GByte 51,539,607,552
64 GByte 68,719,476,736
It is possible that some of the 32 bit operating systems may not allow
you to enter a value larger than the maximum positive signed integer,
namely one less than 2 GByte.


System V memory is part of the Interprocess Communication (IPC) software,
so the letters ipc appear frequently below, along with shm for shared
memory and sem for semaphore.

Many systems will show the current usage by
    ipcs -a
and will allow removal of dead semaphores by
    ipcrm -s mmm -s nnn
where mmm and nnn are the numbers of unused semaphores, accidentally
not cleared up. Defunct semaphores should occur only rarely, if at all.




How to display the settings:
 /sbin/sysctl -a | grep shmmax    shows the limit in bytes
ipcs -l "max seg size" is the same number, in KB
ipcs -a will show current usage information



try to increase your shared memory (root):
./sbin/sysctl -w kernel.shmmax=yourvalue in bytes

Moreover you should post more info about your calculation!

greetings alfred

Forum Vet
Tom
Could you please send us your input file or uploaded to a website?
Thanks, Edo

Quote:Hanlonte Feb 23rd 11:38 am
I'm attempting to run a geometry optimization on a fluoride at the DFT level of theory using the B3LYP functional, ZORA, and ANO-RCC basis set. However I've arrived at the following error and can't for the life of me figure out what it's trying to tell me. The message is:

int_init: internal texas instability possible cando_txs set to always be F
Segmentation fault

Any ideas on how to address this are most appreciated.

Thanks in advance,
Tom


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