Re: Urgent need of (paid) PostgreSQL support in New

>>>>> "TL" == Tom Lane <tgl@sss.pgh.pa.us> writes:

TL> There are varying opinions about that.  Some say "push PG's
TL> shared-buffers setting as high as you can make it".  Some say "use a
TL> conservatively small shared-buffers setting and expect the kernel to use
TL> the rest of physical memory as kernel disk buffers".  But both camps

I think that once your DB size gets big enough, there will be queries
that suck no matter what, because you have to scan through a boatload
of disk pages.  Basically, once your working set size is bigger than
the shared buffer space, you're hosed.  Making shared buffer space
bigger than 50% of RAM will suck, as Tom said.  I used to do that, now
I have about 25-30% of RAM as shared bufs.  It still sucks because the
data size is too big.  I've got the fastest disks I can get, and split
the data across multiple spindles using RAID5 (yes, I could probably
get faster with RAID 1+0 or something, but it is too late for that
now...)


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Vivek Khera, Ph.D.                Khera Communications, Inc.
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