Re: [BUGS] BUG #14635: Query is executed slower on hot standby slavedatabase then on master database - Mailing list pgsql-bugs

On Thu, May  4, 2017 at 10:26:17AM +1000, Haribabu Kommi wrote:
>     The contents of the indexes should be the same, so why is the slave
>     returning so many more rows?  It has to be because the index entries are
>     not marked as killed (known-dead-to-everybody), or not being treated as
>     killed, in the slave.  I vaguely recall that there's a difference in the
>     rules for index entry visibility on slaves, but it's not clear to me why
>     that should be.
>
>
> The index cleanup by the full vacuum and vacuum one page are WAL logged,
> so when they gets replayed on the slave, both the indexes must be same.
>
> May be the WAL didn't replayed on the slave because of conflict transaction?
> Or Any other scenarios it may be different?

We don't WAL-log hint bits.  Could that affect queries running on the
standbys?

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  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
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