Re: Block-level CRC checks

"Joshua D. Drake" <jd@commandprompt.com> writes:

> Jonah H. Harris wrote:
>> On Thu, Oct 30, 2008 at 10:33 AM, Zdenek Kotala <Zdenek.Kotala@sun.com> wrote:
>>> Please, DO NOT MOVE position of page version in PageHeader structure! And
>>> PG_PAGE_LAYOUT_VERSION should be bump to 5.
>>
>> Umm, any in-place upgrade should be capable of handling changes to the
>> page header.  Of, did I miss something significant in the in-place
>
> I thought that was kind of the point of in place upgrade.

Sure, but he has to have a reliable way to tell what version of the page
header he's looking at...

What I'm wondering though -- are we going to make CRCs mandatory? Or set aside
the 4 bytes even if you're not using them? Because if the size of the page
header varies depending on whether you're using CRCs that sounds like it would
be quite a pain.

--  Gregory Stark EnterpriseDB          http://www.enterprisedb.com Ask me about EnterpriseDB's 24x7 Postgres support!