Re: shmget fails on OS X with proper settings

Just a note:
Reducing the amount of default connections to 25 and increasing shmmax
to 40 Mb did not fix the problem.

Interestingly, changing the max_connections values to 25 was not
reflected in the HINT output after postmaster failed to launch, it
still reports max connections as 30.

Thanks,
Chris

On 5/7/07, Christopher S Martin <martin.christopher.s@gmail.com> wrote:
> The shared_buffers and max_connections values are both set to the
> default values (unchanged i the configuration file).  For
> max_connections this is 50, and for the shared_buffers I believe the
> default is 32mb.
>
> Do you suggest setting the shmmax value to 32mb or greater?
>
> Thanks,
> Chris
>
> My development system has 2GB of RAM
>
> On 5/7/07, Prashant Ranjalkar <prashant.ranjalkar@gmail.com> wrote:
> > Hi Chris,
> >
> > Please let me know your shared_buffers & max_connections .
> > How much RAM your sstem has.
> > You have set up your shmmax to 12MB.
> > I hope these DB parameters have larger in values and stopping the allocating
> > of shared memory segments during start up of the database.
> >  if your system has enough memory then set the shmmax to highier value and
> > try again.
> >
> > Hope this will resolve your problem.
> >
> > Regards,
> >
> > Prashant Ranjalkar
> > EnterpriseDB
> >
> >
> >
> >  On 5/7/07, Christopher S Martin <martin.christopher.s@gmail.com> wrote:
> > > No .pid files found in the data directory.
> > > The ipcs output doesn't list anything owned by the postgres user, or by
> > root.
> > >
> > > Thanks,
> > > Chris
> > >
> > >
> > > On 5/7/07, Prashant Ranjalkar < prashant.ranjalkar@gmail.com> wrote:
> > > > Hello,
> > > >
> > > > Please check any .pid file exist in your data directory. If it exists
> > then
> > > > postmaster is running and memory is not freed up.
> > > > Also check
> > > > ipcs -mp
> > > >
> > > > it will give any shared  memory allocated segments if any and consuming
> > the
> > > > memory.
> > > >
> > > > regards
> > > > Prashant Ranjalkar
> > > >
> > > >
> > > > On 5/7/07, Christopher S Martin < martin.christopher.s@gmail.com >
> > wrote:
> > > > > sysctl -a reveals the following:
> > > > > kern.sysv.shmmax: 12582912
> > > > > kern.sysv.shmmin : 1
> > > > > kern.sysv.shmmni: 32
> > > > > kern.sysv.shmseg: 8
> > > > > kern.sysv.shmall: 1024
> > > > > kern.sysv.semmni: 87381
> > > > > kern.sysv.semmns: 87381
> > > > > kern.sysv.semmnu: 87381
> > > > > kern.sysv.semmsl : 87381
> > > > > kern.sysv.semume: 10
> > > > >
> > > > > I am using the sysctl.conf file in /etc to set these values at boot
> > > > > time, but in that file I only have the following entries:
> > > > >
> > > > > kern.sysv.shmmax=12582912
> > > > > kern.sysv.shmmin=1
> > > > > kern.sysv.shmmni=32
> > > > > kern.sysv.shmseg=8
> > > > > kern.sysv.shmall=1024
> > > > >
> > > > > When booting up in unix mode to view the output from all the startup
> > > > > processes, I do notice that it looks like the sysctl values are read
> > > > > and set twice, not sure if this would affect anything.
> > > > >
> > > > > I checked the process listing for any other postmaster processes that
> > > > > could have been left running, but nothing it showing up.  I'm using a
> > > > > LaunchAgent to start postmaster, so it shouldn't be starting on its
> > > > > own anyway.
> > > > >
> > > > > On 5/7/07, Prashant Ranjalkar < prashant.ranjalkar@gmail.com> wrote:
> > > > > > Hello,
> > > > > >
> > > > > > The previously running postmaster process might not closed properly
> > and
> > > > > > released the kernel's memory.
> > > > > > Check for any process running on the server if it exists then kill
> > the
> > > > > > process.here due to unrelease of kernel's memory and while booting
> > the
> > > > > > process is not releasing shared memory hence leading to problems.
> > > > > >
> > > > > > regards
> > > > > > Prashant Ranjalkar
> > > > > > EnterpriseDB
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > > On 5/7/07, Christopher S Martin < martin.christopher.s@gmail.com>
> > wrote:
> > > > > > >
> > > > > > > Martin:
> > > > > > >
> > > > > > > They didn't take any memory out of the machine.  AS for memory
> > cache
> > > > > > > parameters, I'm don't know about that.  How would I go checking
> > for
> > > > > > > that type of thing?
> > > > > > >
> > > > > > > Thanks,
> > > > > > > Chris
> > > > > > >
> > > > > > > On 5/6/07, Martin Gainty < mgainty@hotmail.com > wrote:
> > > > > > > > if you're getting memory errors then a guess would be did they
> > take
> > > > out
> > > > > > any
> > > > > > > > memory out of your machine or perhaps did they change your
> > memory
> > > > cache
> > > > > > > > parameters???
> > > > > > > > Martin
> > > > > > > > This email message and any files transmitted with it contain
> > > > > > confidential
> > > > > > > > information intended only for the person(s) to whom this email
> > > > message
> > > > > > is
> > > > > > > > addressed.  If you have received this email message in error,
> > please
> > > > > > notify
> > > > > > > > the sender immediately by telephone or email and destroy the
> > > > original
> > > > > > > > message without making a copy.  Thank you.
> > > > > > > >
> > > > > > > > ----- Original Message -----
> > > > > > > > From: "Christopher S Martin" < martin.christopher.s@gmail.com >
> > > > > > > > To: <pgsql-general@postgresql.org>
> > > > > > > > Sent: Sunday, May 06, 2007 3:07 PM
> > > > > > > > Subject: [GENERAL] shmget fails on OS X with proper settings
> > > > > > > >
> > > > > > > >
> > > > > > > > > Hi to the list, its my first post.
> > > > > > > > >
> > > > > > > > > I was previous running postgres 8.2.1 on my OS X 10.4.9 laptop
> > > > with no
> > > > > > > > > problems.
> > > > > > > > > After I sent it to apple care, I found that I can no longer
> > start
> > > > the
> > > > > > > > > postmaster daemon.   When I try, I receive the standard shmget
> > > > failed
> > > > > > > > > error message:
> > > > > > > > >
> > > > > > > > > FATAL:  could not create shared memory segment: Cannot
> > allocate
> > > > memory
> > > > > > > > > DETAIL:  Failed system call was shmget(key=5432001,
> > size=4112384,
> > > > > > 03600).
> > > > > > > > > HINT:  This error usually means that PostgreSQL's request for
> > a
> > > > shared
> > > > > > > > > memory segment exceeded available memory or swap space. To
> > reduce
> > > > the
> > > > > > > > > request size (currently 4112384 bytes), reduce PostgreSQL's
> > > > > > > > > shared_buffers parameter (currently 300) and/or its
> > > > max_connections
> > > > > > > > > parameter (currently 30).
> > > > > > > > >
> > > > > > > > > I get this error with either the settings recommended on the
> > > > kernel
> > > > > > > > > resources page:
> > > > > > > > >
> > > > > > > > > kern.sysv.shmmax=4194304
> > > > > > > > > kern.sysv.shmmin=1
> > > > > > > > > kern.sysv.shmmni=32
> > > > > > > > > kern.sysv.shmseg=8
> > > > > > > > > kern.sysv.shmall=1024
> > > > > > > > >
> > > > > > > > > And I also get it when i set kern.sysv.shmmax=12582912
> > > > > > > > >
> > > > > > > > > After making all these changed rebooting doesn't fix anything.
> > > > > > > > >
> > > > > > > > > Has anyone ran into this problem, or has any idea as to why
> > this
> > > > would
> > > > > > > > > start to fail so suddenly?
> > > > > > > > >
> > > > > > > > > Thanks,
> > > > > > > > > Chris
> > > > > > > > >
> > > > > > > > > ---------------------------(end of
> > > > > > broadcast)---------------------------
> > > > > > > > > TIP 4: Have you searched our list archives?
> > > > > > > > >
> > > > > > > > >               http://archives.postgresql.org/
> > > > > > > > >
> > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > > > ---------------------------(end of
> > > > > > broadcast)---------------------------
> > > > > > > TIP 6: explain analyze is your friend
> > > > > > >
> > > > > >
> > > > > >
> > > > >
> > > > > ---------------------------(end of
> > > > broadcast)---------------------------
> > > > > TIP 6: explain analyze is your friend
> > > > >
> > > >
> > > >
> > >
> >
> >
>