This is the mail archive of the cygwin mailing list for the Cygwin project.

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Postgresql error "pg_ctl stop" is invoked after a "postmaster -i &" invocation

Carlo Florendo schrieb:
I invoked:

"postmaster -i -D /var/postgresql/data &"

and was able to start and connect to my database. Since the process was made to run on the background, I wanted a way to stop it without doing a "kill -9". Thus, on another instance of my shell, I invoked :

"pg_ctl stop -D /var/postgresql/data"

Postgres says it was unsuccessful in shutting down the database. However, doing a "ps" revealed that no postgres processes were running.

I then tried to restart the DB once again with:

"postmaster -i -D /var/postgresql/data &"

This time, I got this errror:

$ postmaster -i -D /var/postgresql/data &
FATAL: could not create semaphores: No space left on device
DETAIL: Failed system call was semget(5432004, 17, 03600).
HINT: This error does *not* mean that you have run out of disk space.
It occurs when either the system limit for the maximum number of semaphore sets (SEMMNI), or the system wide maximum number of semaphores (SEMMNS), would be exceeded. You need to raise the respective kernel parameter. Alternatively, reduce PostgreSQL's consumption of semaphores by reducing its max_connections parameter (currently 40).
The PostgreSQL documentation contains more information about configuring your system for PostgreSQL.

I have a lot of diskspace. Doing a "df" revealed:

Now the tricky part: Did you actually read what the error message told you?

Honestly, I know of no other POSIX or Windows app which explains such a basic error in such helpful details. And I thought postgresql is already ready for the dummy mode with the new windows port.

max_connections=40 is a bit high and your SEMMNS are way too low for 40.
5 are recommended for a busy system.

$ nano /etc/cygserver.conf
There you can edit the explained kernel params.

$ df
Reini Urban

Unsubscribe info:
Problem reports:

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]