Re: [HACKERS] Disk block size issues. - Mailing list pgsql-hackers

From darrenk@insightdist.com (Darren King)
Subject Re: [HACKERS] Disk block size issues.
Date
Msg-id 9801092224.AA46582@ceodev
Whole thread Raw
List pgsql-hackers
> On Fri, 9 Jan 1998, Bruce Momjian wrote:
>
> > > Could the block size be made into a command line option, like "-k 8192"?
> >
> > Too scary for me.
>
>     I kinda like this one...if it can be relatively implimented.  The main
> reason I like it is that, like -B and -S, it means that someone could deal
> with "tweaking" a system without having to recompile from scratch...
>
>     That said, I'd much rather that -k option being something that is
> an option only available when *creating* the database (ie. initdb) with a
> pg_blocksize file being created and checked when postmaster starts up.
>
>     Essentially, make '-k 8192' an option only available to the postgres
> process, not the postmaster process.  And not settable by the -O option to
> postmaster...
>
> > Yes, we could do that, but if they ever start the postmaster with a
> > different value, he is lost.
>
>     See above...it should only be something that is settable at initdb time,
> not accessible via 'postmaster' itself...

This is a pretty reasonable restriction, but...

The major change would be like Bruce has stated earlier, the variables that
are declared with the #define value would have to be made into pointers and
palloc'd/pfree'd as necessary.  Could get pretty ugly in files like nbtsort.c
with double-dereferenced pointers and all.

I'll make a list of these variables this weekend and come with a more definate
opinion on the subject.

darrenk

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