Hi Kristian!
On Tue, Jan 10, 2017 at 5:37 PM, Kristian Nielsen <knielsen@knielsen-hq.org> wrote:
> Sachin Setiya <sachin.setiya@mariadb.com> writes:
>
>> Okay, So it there a better way to show progress in slave ?
>
> You have not explained what you mean by "showing progress".
>
> Doesn't SHOW SLAVE STATUS already show event-by-event progress in the relay
> log position?
>
> For progress inside a row event, for example one could display the offset of
> current row operation as a percentage of total event size. Be sure to
> consider the performance impact of such status updates.
>
> Why does replication slave need different progress monitoring than any other
> thread doing queriess?
>
> I mean, more visibility and monitoring is nice, sure. But it should start
> with a general approach and design. Not by randomly adding bits and pieces
> to various binlog events (or other places) without a clear idea what is
> being achieved, and why...
>
> - Kristian.
This task is related to mdev-7409 / mdev-4557.
I have created a patch for this mdev. but I was thinking for monitoring command 'SHOW PROCESSLIST'
in Progress column can we show how much % of the events from Event group Slave has applied so that
user can get a better monitoring.
If I apply my patch I get only this.
MariaDB [d]> show processlist;
+----+-------------+-----------+------+---------+------+-------------------------------------------------+------------------+----------+
| Id | User | Host | db | Command | Time | State | Info | Progress |
+----+-------------+-----------+------+---------+------+-------------------------------------------------+------------------+----------+
| 3 | system user | | d | Connect | 0 | Write_rows_log_event::write_row(-1) on table t1 | NULL | 0.000 |
| 4 | system user | | NULL | Connect | 121 | Waiting for master to send event | NULL | 0.000 |
| 7 | root | localhost | d | Query | 0 | init | show processlist | 0.000 |
+----+-------------+-----------+------+---------+------+-------------------------------------------------+------------------+----------+
Progress is always zero.
So I was thinking if somehow in advace we can know how many events are there in event group we can show progress to
user by calculating how much % of events from Event group we have executed.
Regards
sachin