Skip site navigation (1) Skip section navigation (2)

Re: xlog location arithmetic

From: Robert Haas <robertmhaas(at)gmail(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Peter Eisentraut <peter_e(at)gmx(dot)net>, Magnus Hagander <magnus(at)hagander(dot)net>, Fujii Masao <masao(dot)fujii(at)gmail(dot)com>, Euler Taveira de Oliveira <euler(at)timbira(dot)com>, Pgsql Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: xlog location arithmetic
Date: 2012-03-09 19:39:26
Message-ID: (view raw or whole thread)
Lists: pgsql-hackers
On Fri, Mar 9, 2012 at 2:34 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Fri, Mar 9, 2012 at 2:26 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> Peter Eisentraut <peter_e(at)gmx(dot)net> writes:
>>>> Yeah, the use of XLogFile to mean something other than, well a file in
>>>> the xlog, is greatly annoying.. I guess we could change it, but it
>>>> goes pretty deep in the system so it's not a small change...
>>> The whole thing was built around the lack of 64 bit integers.  If we bit
>>> the bullet and changed the whole thing to be just a single 64-bit
>>> counter, we could probably delete thousands of lines of code.
>> Hm.  I think "thousands" is an overestimate, but yeah the logic could be
>> greatly simplified.  However, I'm not sure we could avoid breaking the
>> existing naming convention for WAL files.  How much do we care about
>> that?
> Probably not very much, since WAL files aren't portable across major
> versions anyway.  But I don't see why you couldn't keep the naming
> convention - there's nothing to prevent you from converting a 64-bit
> integer back into two 32-bit integers if and where needed.

On further reflection, this seems likely to break quite a few
third-party tools.  Maybe it'd be worth it anyway, but it definitely
seems like it would be worth going to at least some minor trouble to
avoid it.

Robert Haas
The Enterprise PostgreSQL Company

In response to


pgsql-hackers by date

Next:From: Robert HaasDate: 2012-03-09 19:41:40
Subject: Re: [v9.2] sepgsql's DROP Permission checks
Previous:From: Kevin GrittnerDate: 2012-03-09 19:37:43
Subject: Re: xlog location arithmetic

Privacy Policy | About PostgreSQL
Copyright © 1996-2015 The PostgreSQL Global Development Group