Re: GIN improvements part 1: additional information

On Mon, Sep 23, 2013 at 12:47 AM, Alexander Korotkov
<aekorotkov(at)gmail(dot)com>wrote:

> It's probably an option to select 64 entries instead of 32.
> There is still some regression in update speed. However, there is also
> room for improvement patch. It searches item index entries 2 times on
> insert: in dataLocateLeafItem and dataPlaceToPage. We can save full results
> of dataLocateLeafItem, but it require some rework of gin btree interface:
> store not only offset of item.
>

In the attached version of patch double finding of ItemPointer during
insert is avoided. Overhead becomes lower as expected.

event | master | 16-entries | 32-entries
| 64-entries | 128-entries |
-----------------------+-----------------+-----------------+-----------------+-----------------+-----------------+
index_build | 00:01:50.042658 | 00:01:54.130873 | 00:01:59.37302
| 00:01:55.959693 | 00:01:58.126407 |
index_build_recovery | 00:00:19 | 00:00:06 | 00:00:06
| 00:00:06 | 00:00:06 |
index_update | 00:05:18.215707 | 00:05:38.40231 |
00:05:30.658786 | 00:05:27.664312 | 00:05:30.815876 |
index_update_recovery | 00:01:48 | 00:01:53 | 00:01:50
| 00:01:44 | 00:01:46 |
search_new | 00:25:21.481699 | 00:23:20.324152 |
00:24:02.120438 | 00:22:50.989723 | 00:23:05.703824 |
search_updated | 00:25:57.622592 | 00:26:43.531979 |
00:26:08.003085 | 00:24:36.669028 | 00:26:09.175243 |

label | size | 16-entries | 32-entries | 64-entries |
128-entries |
---------------+------------+------------+------------+------------+-------------+
new | 884514816 | 417013760 | 421240832 | 430350336 |
450994176 |
after_updates | 1595252736 | 711368704 | 719380480 | 735682560 |
774275072 |

------
With best regards,
Alexander Korotkov.