Re: Controlling CPU Usage in PostgreSQL

On Monday 31 July 2006 10:06, Aaron Bono wrote:
| Is there a way I can tell PostgreSQL to give session a low priority so even
| if it does take the full CPU, it only does so if it would otherwise be
| idle?

the "nice" command might do what you want...

OK, so I tried:

su - postgres -c "nice -n 19 psql my_db"

The problem is, the psql command has a nice value of 19 but the PostgreSQL server process that psql has connected to is running with a nice value of 0.  My assumption is that, if I then run my functions, psql will get low priority but it is the server process that is running with normal priority that will still use up all the CPU.

Bottom line, I am skeptical if this will really achieve my goal - to have the functions run with low priority.

Is there a way to tell PostgreSQL to change the nice value of a particular connection?  I guess I could use renice but that means a lot of shell scripting to determine what PID to change - I am not a shell script expert and would rather not pursue that option.