Re: [PERFORM] Anything to be gained from a 'Postgres Filesystem'?

[Sean Chittenden]

As someone else noted, this doesn't belong in the filesystem (rather 
the kernel's block I/O layer/buffer cache). But I agree, an API by 
which we can tell the kernel what kind of I/O behavior to expect would 
be good.
[snip]
The closest API to what you're describing that I'm aware of is 
posix_fadvise(). While that is technically-speaking a POSIX standard, 
it is not widely implemented (I know Linux 2.6 implements it; based on 
some quick googling, it looks like AIX does too).
Don't forget about the existence/usefulness/widely implemented 
madvise(2)/posix_madvise(2) call, which can give the OS the following 
hints: MADV_NORMAL, MADV_SEQUENTIAL, MADV_RANDOM, MADV_WILLNEED, 
MADV_DONTNEED, and MADV_FREE.  :)  -sc

--
Sean Chittenden

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