Re: pageinspect: Hash index support

From: Jesper Pedersen <jesper(dot)pedersen(at)redhat(dot)com>
To: Michael Paquier <michael(dot)paquier(at)gmail(dot)com>
Cc: Ashutosh Sharma <ashu(dot)coek88(at)gmail(dot)com>, Jeff Janes <jeff(dot)janes(at)gmail(dot)com>, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>, PostgreSQL Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: pageinspect: Hash index support
Date: 2016-09-21 13:30:44
Message-ID: d235dcd6-146a-1269-73a0-da9a55bfeddc@redhat.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On 09/21/2016 08:43 AM, Michael Paquier wrote:
>> page_stats / page_items should not be used on the metadata page.
>>
>> As these functions are marked as superuser only it is expected that people
>> provides the correct input, especially since the raw page structure is used
>> as the input.
>
> btree functions use the block number to do some sanity checks. You
> cannot do that here as only bytea functions are available, but you
> could do it in verify_hash_page by looking at the opaque data and look
> at LH_META_PAGE. Then add a boolean argument into verify_hash_page to
> see if the caller expects a meta page or not and just issue an error.
> Actually it would be a good idea to put in those safeguards, even if I
> agree with you that calling those functions is at the risk of the
> user... Could you update the patch in this sense?
>
> I had fun doing the same tests, aka running the items and stats
> functions on a meta page, and the meta function on a non-meta page,
> but at my surprise I did not see a crash, so perhaps I was lucky and
> perhaps that was because of OSX.
>

Attached is v5, which add basic page verification.

Thanks for the feedback !

Best regards,
Jesper

Attachment Content-Type Size
0001-pageinspect-Hash-index-support_v5.patch text/x-patch 33.5 KB

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Michael Paquier 2016-09-21 14:02:57 Re: Tracking wait event for latches
Previous Message Fabien COELHO 2016-09-21 13:23:46 Re: pgbench - compute & show latency consistently