Re: [HACKERS] postmaster failure with 2-23 snapshot

The Hermit Hacker <scrappy(at)hub(dot)org> writes:

> Is there any way (sysctl?) of determining the max # of semaphores
> configured into a system?

On NetBSD (default configuration; I had to change it for PostgreSQL):

athene:tih> ipcs -S
seminfo:
semmap: 30 (# of entries in semaphore map)
semmni: 10 (# of semaphore identifiers)
semmns: 60 (# of semaphores in system)
semmnu: 30 (# of undo structures in system)
semmsl: 60 (max # of semaphores per id)
semopm: 100 (max # of operations per semop call)
semume: 10 (max # of undo entries per process)
semusz: 100 (size in bytes of undo structure)
semvmx: 32767 (semaphore maximum value)
semaem: 16384 (adjust on exit max value)

athene:tih> ipcs -Q
msginfo:
msgmax: 16384 (max characters in a message)
msgmni: 40 (# of message queues)
msgmnb: 2048 (max characters in a message queue)
msgtql: 40 (max # of messages in system)
msgssz: 8 (size of a message segment)
msgseg: 2048 (# of message segments in system)

athene:tih> ipcs -M
shminfo:
shmmax: 4194304 (max shared memory segment size)
shmmin: 1 (min shared memory segment size)
shmmni: 128 (max number of shared memory identifiers)
shmseg: 32 (max shared memory segments per process)
shmall: 1024 (max amount of shared memory in pages)

> For that matter, being able to do a configure check to see if
> semaphores are even compiled into the system or not (ala FreeBSD)
> might be nice too...

Again, on NetBSD:

athene:tih> sysctl -a | grep sysv
kern.sysvmsg = 1
kern.sysvsem = 1
kern.sysvshm = 1

-tih
--
Popularity is the hallmark of mediocrity. --Niles Crane, "Frasier"