Shared_buffers (25% of RAM / 8KB)) = 8589934592 * .25 / 8192 = 262144
250,000 is probably the max you can use due to the 2GB process limit unless you recompile the Linux Kernel to use 3GB process/1GB kernel. Yes, I've got 8GB also and I started at 262144 and kept working my way down until Linux would allocate the memory.
Sort_mem (4% of RAM / 1KB) = 335544. We'll take about half of that - 167772
Effective_cache_size = 262144 (same as shared_buffers - 25%)
This should reflect the amount of memory available for caching. And unless you plan on running a ton of memory hogging software on the same machine, you probably will have 6GB available as cache. Top on my system confirms the 6GB number so I've got my setting at 750,000. (Left a little space for OS/programs/etc.)
In the /etc/sysctl file:
=================
kernel.shmall = 536870912 (512MB) SHMALL Total amount of shared memory available (bytes or pages)
kernel.shmmax = 536870912 (512MB) SHMMAX Maximum size of shared memory segment (bytes)
Ain't gonna happen unless you recompile the linux kernel to do 3/1. Through trial-and-error, I've found the largest number is:
2,147,483,648
Are the above settings ok to begin with? Are there any other parameters that I should configure now, or monitor lateron?
Above is pretty good. I'd also bump up the free space map settings and maybe try to symlink the pg_xlog directory (log files) to a seperate drive.
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