Re: Microvacuum support for Hash Index

Hi,

On 11/02/2016 01:38 AM, Ashutosh Sharma wrote:
>> While replaying the delete/vacuum record on standby, it can conflict
>> with some already running queries.  Basically the replay can remove
>> some row which can be visible on standby.  You need to resolve
>> conflicts similar to what we do in btree delete records (refer
>> btree_xlog_delete).
>
> Agreed. Thanks for putting this point. I have taken care of it in the
> attached v2 patch.
>

Some initial comments.

_hash_vacuum_one_page:

+        END_CRIT_SECTION();
+        _hash_chgbufaccess(rel, metabuf, HASH_READ, HASH_NOLOCK);

The _hash_chgbufaccess() needs a comment.

You also need a place where you call pfree for so->killedItems - maybe 
in hashkillitems().

Best regards, Jesper