Обсуждение: error report on slru.c

Hi all,
here a patch that
1) Rise the information about the file missing on pg_clog from
    detail to error
2) Insert the offset information also for a missing file


I did it with the 8.0beta2 sources





Regards
Gaetano Mendola


--- slru.c.orig    2004-10-02 10:56:01.000000000 +0200
+++ slru.c    2004-10-02 11:05:40.000000000 +0200
@@ -634,9 +634,8 @@
         case SLRU_OPEN_FAILED:
             ereport(ERROR,
                     (errcode_for_file_access(),
-                errmsg("could not access status of transaction %u", xid),
-                     errdetail("could not open file \"%s\": %m",
-                               path)));
+                errmsg("could not access status of transaction %u"
+                       "could not open file \"%s\": %m ( offset %u ) ", xid, path, offset)));
             break;
         case SLRU_CREATE_FAILED:
             ereport(ERROR,

Gaetano Mendola <mendola@bigfoot.com> writes:
> here a patch that
> 1) Rise the information about the file missing on pg_clog from
>     detail to error

This violates the message style guidelines, IMHO.

> 2) Insert the offset information also for a missing file

It's hardly necessary, since the transaction number tells you everything
you need to know if you really need it, and the offset is certainly not
relevant to a file-open failure.

            regards, tom lane

Tom Lane wrote:
> Gaetano Mendola <mendola@bigfoot.com> writes:
>
>>here a patch that
>>1) Rise the information about the file missing on pg_clog from
>>    detail to error
>
>
> This violates the message style guidelines, IMHO.

Tom, your opinion is not humble but is is really appreciated, however
I think that a missing file is not a "detail" information.

>>2) Insert the offset information also for a missing file
>
>
> It's hardly necessary, since the transaction number tells you everything
> you need to know if you really need it, and the offset is certainly not
> relevant to a file-open failure.

Good to know, how is possible then retrive the informations about the file
needed and the offset without rise the logs detail ?


Regards
Gaetano Mendola

Tom Lane wrote:
> Gaetano Mendola <mendola@bigfoot.com> writes:
> > here a patch that
> > 1) Rise the information about the file missing on pg_clog from
> >     detail to error
>
> This violates the message style guidelines, IMHO.

My first impression is that it should be swapped.  The error is that the
file could not be opened.  The detail is that the files is related to
transaction status information.

--
Peter Eisentraut
http://developer.postgresql.org/~petere/

Peter Eisentraut <peter_e@gmx.net> writes:
> Tom Lane wrote:
>> This violates the message style guidelines, IMHO.

> My first impression is that it should be swapped.  The error is that the
> file could not be opened.  The detail is that the files is related to
> transaction status information.

No, the error is that the transaction status couldn't be accessed.  The
fact that it is stored in a file is implementation detail, and primary
messages should not focus on implementation detail.

            regards, tom lane

Tom Lane wrote:
> Peter Eisentraut <peter_e@gmx.net> writes:
>
>>Tom Lane wrote:
>>
>>>This violates the message style guidelines, IMHO.
>
>
>>My first impression is that it should be swapped.  The error is that the
>>file could not be opened.  The detail is that the files is related to
>>transaction status information.
>
>
> No, the error is that the transaction status couldn't be accessed.  The
> fact that it is stored in a file is implementation detail, and primary
> messages should not focus on implementation detail.

Right, so the only way a DBA have is to look the details! Is there another
way to know the file and the offset a transaction belong to ?



Regards
Gaetano Mendola