On Wed, Apr 20, 2011 at 6:18 AM, Becker, Bernd <span dir="ltr"><<a href="mailto:bernd.becker@metoffice.gov.uk">bernd.becker@metoffice.gov.uk</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<br>
Hello,<br>
<br>
Thanks for the development and provision of the lats interface!<br>
It is really handy and works very well (most of the time)<br>
<br>
I am sub selecting and regridding an ensemble forecast and hindcast.<br>
Lats does it's thing but occasionally , I get<br>
<br>
LATS warning (lats_parmtab: Closing the previously opened Parameter<br>
Table: /home/fred/blogs/misc.table<br>
<br>
<br>
and very occasionally, after about 15-20 minutes and grubbing through<br>
ca 20-40 files, I get<br>
<br>
LATS warning (lats_parmtab): Closing the previously opened Parameter<br>
Table:<br>
/home/fred/blogs/misc.table<br>
/home/fred/blogs/grads/gdopmod.ksh[193]: 496646 Segmentation<br>
fault(coredump)<br>
<br>
<br>
I wonder if this is caused by the following:<br>
in the grads script two files are opened:<br>
the input file and a dummy file to describe the new grid<br>
<br>
'lats4d -v -table /home/fred/blogs/misc.table -de<br>
/home/fred/blogs/dummy.ctl -vars tmin tmax prec mslp z -func<br>
re(@,192,linear,0,1.875,145,linear,-90.00,1.25,ba) -lon 0 357.1875 -o<br>
'outfile' -precision 12 -format grads_grib '<br>
<br>
Now I added a 'sleep 2' to give lats a breather and to sort out all<br>
internal I/O.<br>
<br>
and here I have choice: either<br>
- reinit or<br>
- close 2, close 1<br>
<br>
before the loop goes to the next file.<br>
<br>
But is does not change the error.<br>
<br>
All runs well, singing and dancing for about 20 minutes, then seg<br>
faults.<br>
<br>
Restarting the suite to continue working throught the list of files<br>
works fine for<br>
another batch of files until seg fault.<br>
<br>
<br>
What is there to try to pin point the problem?<br></blockquote><div><br></div><div>Hmm... Very strange. This sort of problem usually indicates a memory leak somewhere. Sometimes you simply get a segfault when you run out of memory. If you are on a linux/unix environment, open a second window and start the "top" command and watch the memory usage of your application (on Windows, watch your memory usage from the task manager with ctrl-alt-del). If it keeps going up until it segfaults this will confirm the memory leak. As for fixing it, it will require some detective work by the developers.</div>
<div><br></div><div>I myself use the lats4d.sh script and issue the command from the shell script, usually one file at a time.</div><div><br></div><div> Arlindo</div><div><br></div></div>-- <br>Arlindo da Silva<br><a href="mailto:dasilva@alum.mit.edu">dasilva@alum.mit.edu</a><br>