Since there appears to be a one to one relationship between backend
processes and connected users, what options are there for shops that have
more than 64 users?
-----Original Message-----From: Tom Lane [SMTP:tgl@sss.pgh.pa.us]Sent: Monday, February 22, 1999 8:10 AMTo:
BruceMomjianCc: pgsql-hackers@postgreSQL.orgSubject: Re: [HACKERS] Re: Max backend limits cleaned up
Bruce Momjian <maillist@candle.pha.pa.us> writes:> I am getting:> IpcSemaphoreCreate: semget failed (No space left on
device)
key=5432017,> num=16, permission=600> [ later ]> I got it working by adding a -N 32 to the postmaster startup.
Looks> like my site BSD/OS can't start 64 backends. Some of my
configuration> is wrong. Perhaps we need 32 as the default.
Yeah, I was thinking about that myself. I left the default -N
settingat 64 on the theory that people who had gone to the trouble of
makingsure they had proper kernel configurations should not get surprised
byv6.5 suddenly reducing the default number-of-backends limit.
On the other hand, we have reason to believe that a lot of systems
arenot configured to allow Postgres to grab 64 semaphores, so if we
don'treduce the default -N value we will almost certainly see a lot of
gripesjust like the above when people move to 6.5. (I think -N 32 would
workas a default on minimally-configured systems, but cannot prove it.)
I haven't got a real strong feeling either way. Opinions?
regards, tom lane