Hello SPI_finish try to release resources and memory. Maybe you has broken memory. Try to compile postgres with --enable-debug and --enable-cassert flags. You can take more info from core dump. Regards Pavel Stehule 2011/3/23 Jorge ArÃvalo <jorge.arevalo@xxxxxxxxxxxxxxxx>: > Hello, > > I'm writing my own C-function on server side, to extend SQL. One of my > function's arguments is any valid PostgreSQL expression returning a > number. Another argument is a specific data type (RASTER type). So, if > I execute this function against a table with 1000 rows, each row > having one RASTER column, the function does the next for each row: > > - Connects the function to the SPI manager (SPI_connect) > - Executes the expression (SPI_exec) > - Gets the result, 1 number (SPI_getvalue) > - Uses the result with the data type RASTER (not important) > - Frees the memory for the row returned (SPI_freetuptable) > - Disconnect the function from SPI manager (SPI_finish) > > The operations made with the returned result and the RASTER object > involve some memory allocations made in fcinfo->flinfo->fn_mcxt memory > context, but the memory is explicitly released. > > The problem is sometimes the function causes a segmentation fault just > in the SPI_finish call. I've changed the log system according with > http://www.postgresql.org/docs/8.4/static/runtime-config-logging.html, > but there's no more information: Segmentation fault caused for a > SIGSEV signal. > > As the crash is caused only with big tables (thousands of rows), I > thought in a cumulative memory problem, but I free all the memory > allocated out of the function's context, and correct me if I'm wrong, > but the memory allocated with palloc in the function's context is > automatically freed when it finishes. > > So, my questions are: > > - What can be the cause that make SPI_finish to crash by a SIGSEV signal? > - What can I do for getting more information about the crash? I > thought in attaching gdb to the postgres process (PostgreSQL Server > 8.4.6 in Ubuntu Linux machine). Just like this > http://www.mail-archive.com/pgsql-general@xxxxxxxxxxxxxx/msg79320.html > > Thanks in advance, > > -- > Jorge ArÃvalo > Internet & Mobilty Division, DEIMOS > jorge.arevalo@xxxxxxxxxxxxxxxx > http://es.linkedin.com/in/jorgearevalo80 > http://mobility.grupodeimos.com/ > http://gis4free.wordpress.com > http://geohash.org/ezjqgrgzz0g > > -- > Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-general > -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
