Re: Autovacuum launcher occurs error when cancelled by SIGINT

On Wed, Jun 21, 2017 at 7:52 PM, Dilip Kumar <dilipbalaut(at)gmail(dot)com> wrote:
> On Wed, Jun 21, 2017 at 7:47 PM, Kuntal Ghosh
> <kuntalghosh(dot)2007(at)gmail(dot)com> wrote:
>>> IMHO, It's not a good idea to use DSM call to verify the DSA handle.
>>>
>> Okay. Is there any particular scenario you've in mind where this may fail?
>
> It's not about failure, but about the abstraction. When we are using
> the DSA we should not directly access the DSM which is under DSA.
>
Okay. I thought that I've found at least one usage of
dsm_find_mapping() in the code. :-)

But, I've some more doubts.
1. When should we use dsm_find_mapping()? (The first few lines of
dsm_attach is same as dsm_find_mapping().)
2. As a user of dsa, how should we check whether my dsa handle is
already attached? I guess this is required because, if a user tries to
re-attach a dsa handle, it's punishing the user by throwing an error
and the user wants to avoid such errors.

--
Thanks & Regards,
Kuntal Ghosh
EnterpriseDB: http://www.enterprisedb.com