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

The Hermit Hacker <scrappy@hub.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
undoentries per process)       semusz:    100  (size in bytes of undo structure)       semvmx:  32767  (semaphore
maximumvalue)       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
(sizeof 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"