Re: [ADMIN] Postgres shared memory error
On Sat, Apr 28, 2012 at 13:10, Kevin Kempter cs_...@consistentstate.comwrote: All; I just want to be sure that I'm not causing myself greif. I have a kvm in the cloud that is supposed to have access to 32GB of ram. when I do a top I only see 1GB of ram, I've pinged the hosting provider, maybe it shows up as it's used? What does the 'free' command show? Anyway when I try and start postgres I see this: * $ 2012-04-28 12:00:33 EDT [6429]: [1-1] FATAL: XX000: could not create shared memory segment: Cannot allocate memory 2012-04-28 12:00:33 EDT [6429]: [2-1] DETAIL: Failed system call was shmget(key=5432001, size=7700914176, 03600). 2012-04-28 12:00:33 EDT [6429]: [3-1] 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 7700914176 bytes), reduce PostgreSQL's shared_buffers parameter (currently 917504) and/or its max_connections parameter (currently 503). The PostgreSQL documentation contains more information about shared memory configuration. 2012-04-28 12:00:33 EDT [6429]: [4-1] LOCATION: InternalIpcMemoryCreate, pg_shmem.c:178 * Which means I should bump up shmmax like this: *# sysctl -w kernel.shmmax=7700914176* and add it to /etc/sysctl.conf: *# tail /etc/sysctl.conf kernel.msgmax = 65536 # Controls the maximum shared segment size, in bytes kernel.shmmax = 68719476736 # Controls the maximum number of shared memory segments, in pages kernel.shmall = 4294967296 #PostgreSQL kernel.shmmax = 7700914176 * I assume I should have to tweak ONLY kernel.shmmax, am I correct? Correct. I'm also assuming that this is a KVM cloud host provider issue, i.e. it looks like I actually do not have 32G or ram. Does anyone disagree with my conclusions? You haven't provided evidence on how much RAM your system sees. A free -m will show the total memory the system has and is being used. Regards.
Re: [ADMIN] Postgres shared memory error
On 04/28/2012 10:32 AM, Fernando Hevia wrote: On Sat, Apr 28, 2012 at 13:10, Kevin Kempter cs_...@consistentstate.com mailto:cs_...@consistentstate.com wrote: All; I just want to be sure that I'm not causing myself greif. I have a kvm in the cloud that is supposed to have access to 32GB of ram. when I do a top I only see 1GB of ram, I've pinged the hosting provider, maybe it shows up as it's used? What does the 'free' command show? Anyway when I try and start postgres I see this: / $ 2012-04-28 12:00:33 EDT [6429]: [1-1] FATAL: XX000: could not create shared memory segment: Cannot allocate memory 2012-04-28 12:00:33 EDT [6429]: [2-1] DETAIL: Failed system call was shmget(key=5432001, size=7700914176, 03600). 2012-04-28 12:00:33 EDT [6429]: [3-1] 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 7700914176 bytes), reduce PostgreSQL's shared_buffers parameter (currently 917504) and/or its max_connections parameter (currently 503). The PostgreSQL documentation contains more information about shared memory configuration. 2012-04-28 12:00:33 EDT [6429]: [4-1] LOCATION: InternalIpcMemoryCreate, pg_shmem.c:178 / Which means I should bump up shmmax like this: /# sysctl -w kernel.shmmax=7700914176/ and add it to /etc/sysctl.conf: /# tail /etc/sysctl.conf kernel.msgmax = 65536 # Controls the maximum shared segment size, in bytes kernel.shmmax = 68719476736 # Controls the maximum number of shared memory segments, in pages kernel.shmall = 4294967296 #PostgreSQL kernel.shmmax = 7700914176 / I assume I should have to tweak ONLY kernel.shmmax, am I correct? Correct. I'm also assuming that this is a KVM cloud host provider issue, i.e. it looks like I actually do not have 32G or ram. Does anyone disagree with my conclusions? You haven't provided evidence on how much RAM your system sees. A free -m will show the total memory the system has and is being used. Regards. Free command: / # free total used free sharedbuffers cached Mem: 1020856 946804 74052 0 61280 796004 -/+ buffers/cache: 89520 931336 Swap:0 0 0/
Re: [ADMIN] Postgres shared memory error
On Sat, Apr 28, 2012 at 13:37, Kevin Kempter cs_...@consistentstate.comwrote: Free command: * # free total used free sharedbuffers cached Mem: 1020856 946804 74052 0 61280 796004 -/+ buffers/cache: 89520 931336 Swap:0 0 0* You are right. Your system has only 1 GB RAM.
