g98l problems

uccatvm uccatvm at ucl.ac.uk
Thu Nov 28 05:13:58 EST 2002

Hi Luis,

> shmget failed.
> shmget failed.: Invalid argument

The Linux kernel has traditionally fairly small limit for the shared
memory segment size (SHMMAX), and this needs to be increased. On my
dual Xeon (with 2 Gb memory) I have set it to 0.5 Gig, while on some
other 2Gb Xeons in our department it is set to 1Gb. This seems to work

The way to do it permanently is to put (as root) the lines

# Increase max shared memory

into /etc/sysctl.conf before rebooting.

The temporary solution is

echo 536870912 > /proc/sys/kernel/shmmax

Hope this helps,

   Tanja van Mourik                                                
   Royal Society University Research Fellow
   Chemistry Department 
   University College London  phone:  +44 (0)20-7679-4663      
   20 Gordon Street          e-mail: work: T.vanMourik at ucl.ac.uk 
   London WC1H 0AJ, UK               home: tanja_van_mourik at btopenworld.com

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