Re: Block_Size on NTFS

postgresqlgeneral(dot)domain(dot)thewild_codata(at)spamgourmet(dot)com wrote:
> Bruce Momjian - postgresqlgeneral(dot)domain(dot)thewild_codata(at)spamgourmet(dot)com a ?crit :
> > postgresqlgeneral(dot)domain(dot)thewild_codata(at)spamgourmet(dot)com wrote:
> >> Reading through the list of settings returned by "SHOW ALL", I noticed
> >> the "block_size" variable, which defaults to 8192.
> >>
> >> Running on Windows Server, my data directory is on an NTFS partition.
> >> Running CHKDSK on this partition tells me that there are "4096 bytes in
> >> each allocation unit."
> >>
> >> Are these allocation units the same as the "block_size", or does this
> >> only have to do with disk geometry ?
> >> If they are the same, is it important that they match ?
> >
> > It is not necessary they match. It just means that Postgres extends
> > files in 8k chunks while your file system extends them in 4k chunks.
>
> Thanks for your answer Bruce.
> So I guess it is good practice to have postgresql's "block_size" set to
> an exact multiplie of the filesystem's block_size, right ?

Yes.

--
Bruce Momjian <postgresqlgeneral(dot)domain(dot)thewild_codata(at)spamgourmet(dot)com> http://momjian.us
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