Re: Funny hang on PostgreSQL 10 during parallel index scan on slave

Will submit a patch here shortly. Thanks! Should we do for master and
10? Or 9.6 too?

On Wed, Sep 5, 2018 at 6:40 PM Chris Travers <chris(dot)travers(at)adjust(dot)com>
wrote:

> Yep, Maybe we should check for signals there.
>
> On Wed, Sep 5, 2018 at 5:27 PM Thomas Munro <thomas(dot)munro(at)enterprisedb(dot)com>
> wrote:
>
>> On Wed, Sep 5, 2018 at 8:23 AM Chris Travers <chris(dot)travers(at)adjust(dot)com>
>> wrote:
>> > 1. The query is in a parallel index scan or similar
>> > 2. A process is executing a parallel plan and allocating a significant
>> chunk of memory (2MB for example) in dynamic shared memory.
>> > 3. The startup process goes into a loop where it sends a sigusr1,
>> sleeps 5m, and sends another sigusr1 etc.
>> > 4. The sigusr1 aborts the system call, which is then retried.
>> > 5. Because the system call takes more than 5ms, we end up in an
>> endless loop
>>
>> Do you mean this loop in dsm_impl_posix_resize() is getting
>> interrupted constantly and never completing?
>>
>> /* We may get interrupted, if so just retry. */
>> do
>> {
>> rc = posix_fallocate(fd, 0, size);
>> } while (rc == EINTR);
>>
>> --
>> Thomas Munro
>> http://www.enterprisedb.com
>>
>
>
> --
> Best Regards,
> Chris Travers
> Head of Database
>
> Tel: +49 162 9037 210 | Skype: einhverfr | www.adjust.com
> Saarbrücker Straße 37a, 10405 Berlin
>
>

--
Best Regards,
Chris Travers
Head of Database

Tel: +49 162 9037 210 | Skype: einhverfr | www.adjust.com
Saarbrücker Straße 37a, 10405 Berlin