| From: | Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> |
|---|---|
| To: | Pavan Deolasee <pavan(dot)deolasee(at)gmail(dot)com> |
| Cc: | Amit Langote <Langote_Amit_f8(at)lab(dot)ntt(dot)co(dot)jp>, Etsuro Fujita <fujita(dot)etsuro(at)lab(dot)ntt(dot)co(dot)jp>, Albe Laurenz <laurenz(dot)albe(at)wien(dot)gv(dot)at>, Robert Haas <robertmhaas(at)gmail(dot)com>, Andres Freund <andres(at)anarazel(dot)de>, Bruce Momjian <bruce(at)momjian(dot)us>, Josh Berkus <josh(at)agliodbs(dot)com>, Mason S <masonlists(at)gmail(dot)com>, Oleg Bartunov <obartunov(at)gmail(dot)com>, Simon Riggs <simon(at)2ndquadrant(dot)com>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Horizontal scalability/sharding |
| Date: | 2015-09-02 11:42:42 |
| Message-ID: | CAA4eK1KNNbn+a8DM+6FBSjV5J3cjb4e3uE2iGDOuqqqzvnaSMg@mail.gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On Wed, Sep 2, 2015 at 4:19 PM, Pavan Deolasee <pavan(dot)deolasee(at)gmail(dot)com>
wrote:
> On Wed, Sep 2, 2015 at 3:55 PM, Amit Langote <
Langote_Amit_f8(at)lab(dot)ntt(dot)co(dot)jp> wrote:
>>
>> On 2015-09-02 PM 06:41, Amit Langote wrote:
>>
>> Which, I now realize, is not the worry Amit Kapila's expresses.
>>
>> The deadlock was *indeed detected* in this case, with all the locks in
the
>> same PG instance. In a sharded environment with multiple PG instances,
>> that becomes tricky. DLM (distributed lock manager/deadlock detector)
>> seems indeed necessary as Amit K. suspects.
>>
>
> Right. XC/XL did not address this issue and they rely on statement
timeouts to break distributed deadlocks.
>
I think that will be difficult for application to decide and then it
needs to decide the same for all statements which is tricky because
different statements could take different time. I think it is better to
have solution for this problem and deadlock should be detected.
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Fujii Masao | 2015-09-02 12:02:33 | Re: synchronous_commit = apply |
| Previous Message | Fujii Masao | 2015-09-02 11:26:41 | Re: FSM versus GIN pending list bloat |