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Hi, I have several databases. They are each about 35gb in
size and have about 10.5K relations (count from pg_stat_all_tables) in them.
Pg_class is about 26k rows and the data directory contains about 70k files.
These are busy machines, they run about 50 xactions per second, ( aproxx insert
/ update / delete about 500 rows per second). We started getting errors about the number of open file descriptors : 2007-05-09 03:07:50.083 GMT 1146975740: LOG: 53000:
out of file descriptors: Too many open files; release and retry 2007-05-09 03:07:50.083 GMT 1146975740: CONTEXT: SQL
statement "insert ….. " PL/pgSQL function
"trigfunc_whatever" line 50 at execute statement 2007-05-09 03:07:50.083 GMT 1146975740: LOCATION:
BasicOpenFile, fd.c:471 2007-05-09 03:07:50.091 GMT 0: LOG: 00000: duration:
12.362 ms 2007-05-09 03:07:50.091 GMT 0: LOCATION:
exec_simple_query, postgres.c:1090 So we decreased the max_files_per_process to 800.
This took care of the error *BUT* about quadrupled the IO wait
that is happening on the machine. It went from a peek of about 50% to peeks of
over 200% (4 processor machines, 4 gigs ram, raid). The load on the
machine remained constant. I am really to get an understanding of exactly what this
setting is and ‘what’ is out of file descriptors and how I can fix
that. I need to bring that IO back down. Thanks for any help. Ralph -- |
