Re: Should mdxxx functions(e.g. mdread, mdwrite, mdsync etc) PANIC instead of ERROR when I/O failed? - Mailing list pgsql-hackers

From Martijn van Oosterhout
Subject Re: Should mdxxx functions(e.g. mdread, mdwrite, mdsync etc) PANIC instead of ERROR when I/O failed?
Date
Msg-id 20090615112647.GA22208@svana.org
Whole thread Raw
In response to Should mdxxx functions(e.g. mdread, mdwrite, mdsync etc) PANIC instead of ERROR when I/O failed?  ("Jacky Leng" <lengjianquan@163.com>)
Responses Re: Should mdxxx functions(e.g. mdread, mdwrite, mdsync etc) PANIC instead of ERROR when I/O failed?  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
On Mon, Jun 15, 2009 at 04:41:42PM +0800, Jacky Leng wrote:
>   My question is: should not mdxxx functions(e.g. mdread, mdwrite, mdsync)
> just report PANIC instead of ERROR when I/O failed? IMO, since the data has
> already corrupted, reporting ERROR will just leave us a very curious scene
> later -- which does more harm that benefit.

I think the reasoning is that if those functions reported a PANIC the
chance you could recover your data is zero, because you need the
database system to read the other (good) data.

With an ERROR you can investigate the problem and save what can de
saved...

Have a nice day,
--
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> Please line up in a tree and maintain the heap invariant while
> boarding. Thank you for flying nlogn airlines.

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