Maniphest T239192

WMFTimeoutException in Wikidata recentchanges
Closed, DeclinedPublicPRODUCTION ERROR
Actions

Description

Problem:

If you combine many filters the page will not load.

Note:

Also true for Wikipedia.

Solution:

Set max limit to 100?

Example:

https://www.wikidata.org/wiki/Special:RecentChanges?hidebots=1&reviewStatus=unpatrolled&hidepreviousrevisions=1&hidecategorization=1&namespace=12%3B120%3B146%3B640%3B828&limit=100&days=30&enhanced=1&urlversion=2
(not working)

Original:

Error message

[XdzZwApAICMAAJF8grcAAAAJ] 2019-11-26 07:53:33: Fatal exception of type "WMFTimeoutException"

trace

#0 /srv/mediawiki/php-1.35.0-wmf.5/includes/exception/MWExceptionHandler.php(200): {closure}(integer)
#1 [internal function]: MWExceptionHandler::handleError(integer, string, string, integer, array)
#2 /srv/mediawiki/php-1.35.0-wmf.5/includes/libs/rdbms/database/DatabaseMysqli.php(46): mysqli->query(string)
#3 /srv/mediawiki/php-1.35.0-wmf.5/includes/libs/rdbms/database/Database.php(1308): Wikimedia\Rdbms\DatabaseMysqli->doQuery(string)
#4 /srv/mediawiki/php-1.35.0-wmf.5/includes/libs/rdbms/database/Database.php(1226): Wikimedia\Rdbms\Database->executeQueryAttempt(string, string, boolean, string, integer)
#5 /srv/mediawiki/php-1.35.0-wmf.5/includes/libs/rdbms/database/Database.php(1162): Wikimedia\Rdbms\Database->executeQuery(string, string, integer)
#6 /srv/mediawiki/php-1.35.0-wmf.5/includes/libs/rdbms/database/Database.php(1828): Wikimedia\Rdbms\Database->query(string, string)
#7 /srv/mediawiki/php-1.35.0-wmf.5/includes/libs/rdbms/database/DBConnRef.php(68): Wikimedia\Rdbms\Database->select(array, array, array, string, array, array)
#8 /srv/mediawiki/php-1.35.0-wmf.5/includes/libs/rdbms/database/DBConnRef.php(318): Wikimedia\Rdbms\DBConnRef->__call(string, array)
#9 /srv/mediawiki/php-1.35.0-wmf.5/includes/specials/SpecialRecentChanges.php(349): Wikimedia\Rdbms\DBConnRef->select(array, array, array, string, array, array)
#10 /srv/mediawiki/php-1.35.0-wmf.5/includes/specialpage/ChangesListSpecialPage.php(1024): SpecialRecentChanges->doMainQuery(array, array, array, array, array, FormOptions)
#11 /srv/mediawiki/php-1.35.0-wmf.5/includes/specialpage/ChangesListSpecialPage.php(629): ChangesListSpecialPage->getRows()
#12 /srv/mediawiki/php-1.35.0-wmf.5/includes/specials/SpecialRecentChanges.php(165): ChangesListSpecialPage->execute(NULL)
#13 /srv/mediawiki/php-1.35.0-wmf.5/includes/specialpage/SpecialPage.php(575): SpecialRecentChanges->execute(NULL)
#14 /srv/mediawiki/php-1.35.0-wmf.5/includes/specialpage/SpecialPageFactory.php(607): SpecialPage->run(NULL)
#15 /srv/mediawiki/php-1.35.0-wmf.5/includes/MediaWiki.php(298): MediaWiki\Special\SpecialPageFactory->executePath(Title, RequestContext)
#16 /srv/mediawiki/php-1.35.0-wmf.5/includes/MediaWiki.php(967): MediaWiki->performRequest()
#17 /srv/mediawiki/php-1.35.0-wmf.5/includes/MediaWiki.php(530): MediaWiki->main()
#18 /srv/mediawiki/php-1.35.0-wmf.5/index.php(46): MediaWiki->run()
#19 /srv/mediawiki/w/index.php(3): require(string)
#20 {main}

Impact

Unable to see the recent changes with the filters applied

Details

Request ID: XdzZwApAICMAAJF8grcAAAAJ
Request URL: https://www.wikidata.org/wiki/Special:RecentChanges?hidebots=1&reviewStatus=unpatrolled&hidepreviousrevisions=1&hidecategorization=1&namespace=12%3B120%3B146%3B640%3B828&limit=500&days=30&enhanced=1&urlversion=2

Related Objects

Mentioned In: T311360: RecentChanges timing out
T307328: Scalability issues of recentchanges table
T298847: Access to Watchlist in Wikidata returns a Fatal exception of type "Wikimedia\Rdbms\DBQueryError" (due to too many objects?)
T276699: Loading RC on en.wikipedia with a specific set of filters throws out an exception
Mentioned Here: T307328: Scalability issues of recentchanges table
P10177 (An Untitled Masterwork)

Event Timeline

DannyS712 created this task.Nov 26 2019, 7:55 AM

Restricted Application added projects: Growth-Team, User-DannyS712. · View Herald TranscriptNov 26 2019, 7:55 AM

Restricted Application added a subscriber: Aklapper. · View Herald Transcript

DannyS712 moved this task from Unsorted to Reports on the User-DannyS712 board.Nov 26 2019, 7:56 AM

Aklapper added a project: Performance Issue.Nov 26 2019, 4:09 PM

Aklapper edited Stack Trace. (Show Details)

The query works with a smaller limit on result and days
https://www.wikidata.org/wiki/Special:RecentChanges?hidebots=1&reviewStatus=unpatrolled&hidepreviousrevisions=1&hidecategorization=1&namespace=12%3B120%3B146%3B640%3B828&limit=1&days=1&enhanced=1&urlversion=2

It works also for a single namespace
https://www.wikidata.org/wiki/Special:RecentChanges?hidebots=1&reviewStatus=unpatrolled&hidepreviousrevisions=1&hidecategorization=1&namespace=12&limit=500&days=30&enhanced=1&urlversion=2

SQL should look like

SELECT rc_id, 
       rc_timestamp, 
       rc_namespace, 
       rc_title, 
       rc_minor, 
       rc_bot, 
       rc_new, 
       rc_cur_id, 
       rc_this_oldid, 
       rc_last_oldid, 
       rc_type, 
       rc_source, 
       rc_patrolled, 
       rc_ip, 
       rc_old_len, 
       rc_new_len, 
       rc_deleted, 
       rc_logid, 
       rc_log_type, 
       rc_log_action, 
       rc_params, 
       comment_rc_comment.comment_text AS `rc_comment_text`, 
       comment_rc_comment.comment_data AS `rc_comment_data`, 
       comment_rc_comment.comment_id   AS `rc_comment_cid`, 
       actor_rc_user.actor_user        AS `rc_user`, 
       actor_rc_user.actor_name        AS `rc_user_text`, 
       rc_actor, 
       page_latest, 
       (SELECT Group_concat(ctd_name SEPARATOR ',') 
        FROM   `change_tag` 
               JOIN `change_tag_def` 
                 ON (( ct_tag_id = ctd_id )) 
        WHERE  ct_rc_id = rc_id)       AS `ts_tags` 
FROM   `recentchanges` 
       JOIN `comment` `comment_rc_comment` 
         ON (( comment_rc_comment.comment_id = rc_comment_id )) 
       JOIN `actor` `actor_rc_user` 
         ON (( actor_rc_user.actor_id = rc_actor )) 
       LEFT JOIN `page` 
              ON (( rc_cur_id = page_id )) 
WHERE  rc_bot = 0 
       AND ( ( rc_this_oldid = page_latest ) 
              OR rc_type = 3 ) 
       AND ( rc_type != 6 ) 
       AND rc_patrolled = 0 
       AND ( rc_namespace IN ( '12', '120', '146', '640', '828' ) ) 
       AND ( rc_timestamp >= '20191030201706' ) 
       AND rc_new IN ( 0, 1 ) 
ORDER  BY rc_timestamp DESC 
LIMIT  500

At it seems the database choose rc_ns_actor here which sounds not bad:

-- Probably intended for Special:NewPages namespace filter
CREATE INDEX /*i*/rc_ns_actor ON /*_*/recentchanges (rc_namespace, rc_actor);

Maybe in production it use another index without the namespace column.
The selected namespaces here have less pages, so a index without namespace may have to read many rows from the recentchanges table

12 - Help
120 - Property
146 - Lexeme
640 - EntitySchema
828 - Module

Krinkle moved this task from Untriaged to Nov2019/1.35.wmf.5+ on the Wikimedia-production-error board.Dec 4 2019, 12:36 AM

Krinkle added a project: Wikidata-Campsite.

Krinkle updated the task description. (Show Details)

Krinkle edited Stack Trace. (Show Details)

Running the query in the comment above on an analytics slave produced a result in 1 min 12.26 sec
Trying the example URL provided the page loaded after 2 mins.

Addshore triaged this task as Low priority.Jan 14 2020, 1:46 PM

Looks like a different index would be beneficial here...

The query posted above.

+------+--------------------+--------------------+--------+----------------------------------------------------------------------------------------------------------------------------------------------+----------------------+---------+------------------------------------------+---------+-------------+
| id   | select_type        | table              | type   | possible_keys                                                                                                                                | key                  | key_len | ref                                      | rows    | Extra       |
+------+--------------------+--------------------+--------+----------------------------------------------------------------------------------------------------------------------------------------------+----------------------+---------+------------------------------------------+---------+-------------+
|    1 | PRIMARY            | recentchanges      | range  | rc_timestamp,new_name_timestamp,tmp_2,tmp_3,rc_name_type_patrolled_timestamp,rc_ns_actor,rc_actor,rc_namespace_title_timestamp,rc_this_oldid | rc_timestamp         | 16      | NULL                                     | 9830478 | Using where |
|    1 | PRIMARY            | actor_rc_user      | eq_ref | PRIMARY                                                                                                                                      | PRIMARY              | 8       | wikidatawiki.recentchanges.rc_actor      |       1 |             |
|    1 | PRIMARY            | page               | eq_ref | PRIMARY                                                                                                                                      | PRIMARY              | 4       | wikidatawiki.recentchanges.rc_cur_id     |       1 | Using where |
|    1 | PRIMARY            | comment_rc_comment | eq_ref | PRIMARY                                                                                                                                      | PRIMARY              | 8       | wikidatawiki.recentchanges.rc_comment_id |       1 |             |
|    2 | DEPENDENT SUBQUERY | change_tag         | ref    | change_tag_rc_tag_id,change_tag_tag_id_id                                                                                                    | change_tag_rc_tag_id | 5       | wikidatawiki.recentchanges.rc_id         |       1 | Using index |
|    2 | DEPENDENT SUBQUERY | change_tag_def     | eq_ref | PRIMARY                                                                                                                                      | PRIMARY              | 4       | wikidatawiki.change_tag.ct_tag_id        |       1 |             |
+------+--------------------+--------------------+--------+----------------------------------------------------------------------------------------------------------------------------------------------+----------------------+---------+------------------------------------------+---------+-------------+

With FORCE INDEX (tmp_3) on recentchanges it returns in 3.5 seconds.

+------+--------------------+--------------------+--------+-------------------------------------------+----------------------+---------+------------------------------------------+--------+----------------------------------------------------+
| id   | select_type        | table              | type   | possible_keys                             | key                  | key_len | ref                                      | rows   | Extra
                                     |
+------+--------------------+--------------------+--------+-------------------------------------------+----------------------+---------+------------------------------------------+--------+----------------------------------------------------+
|    1 | PRIMARY            | recentchanges      | range  | tmp_3                                     | tmp_3                | 20      | NULL                                     | 347046 | Using index condition; Using where; Using filesort |
|    1 | PRIMARY            | actor_rc_user      | eq_ref | PRIMARY                                   | PRIMARY              | 8       | wikidatawiki.recentchanges.rc_actor      |      1 |
                                     |
|    1 | PRIMARY            | page               | eq_ref | PRIMARY                                   | PRIMARY              | 4       | wikidatawiki.recentchanges.rc_cur_id     |      1 | Using where
                                     |
|    1 | PRIMARY            | comment_rc_comment | eq_ref | PRIMARY                                   | PRIMARY              | 8       | wikidatawiki.recentchanges.rc_comment_id |      1 |
                                     |
|    2 | DEPENDENT SUBQUERY | change_tag         | ref    | change_tag_rc_tag_id,change_tag_tag_id_id | change_tag_rc_tag_id | 5       | wikidatawiki.recentchanges.rc_id         |      1 | Using index
                                     |
|    2 | DEPENDENT SUBQUERY | change_tag_def     | eq_ref | PRIMARY                                   | PRIMARY              | 4       | wikidatawiki.change_tag.ct_tag_id        |      1 |
                                     |
+------+--------------------+--------------------+--------+-------------------------------------------+----------------------+---------+------------------------------------------+--------+----------------------------------------------------+

Addshore moved this task from incoming to needs discussion or investigation on the Wikidata board.Jan 14 2020, 2:30 PM

Addshore added a subscriber: Ladsgroup.

Some that are actually provided by mediawiki also work well with USE INDEX:

new_name_timestamp   | 21      | NULL                                     | 369847 | Using index condition; Using where; Using filesort
rc_name_type_patrolled_timestamp          | rc_name_type_patrolled_timestamp | 5       | NULL                                     | 340237 | Using index condition; Using where; Using filesort
rc_namespace_title_timestamp              | rc_namespace_title_timestamp | 4       | NULL                                     | 456781 | Using index condition; Using where; Using filesort

"Using index condition; Using where; Using filesort" that's sad and slow but it works because the range is small.

but I agree timestamp index does make sense for most wikis but not wikidata.

The query I got from tendril is:

SELECT /* SpecialRecentChanges::doMainQuery */ rc_id, rc_timestamp, rc_namespace, rc_title, rc_minor, rc_bot, rc_new, rc_cur_id, rc_this_oldid, rc_last_oldid, rc_type, rc_source, rc_patrolled, rc_ip, rc_old_len, rc_new_len, rc_deleted, rc_logid, rc_log_type, rc_log_action, rc_params, comment_rc_comment.comment_text AS `rc_comment_text`, comment_rc_comment.comment_data AS `rc_comment_data`, comment_rc_comment.comment_id AS `rc_comment_cid`, actor_rc_user.actor_user AS `rc_user`, actor_rc_user.actor_name AS `rc_user_text`, rc_actor, wl_user, wl_notificationtimestamp, page_latest, (SELECT GROUP_CONCAT(ctd_name SEPARATOR ', ') FROM `change_tag` JOIN `change_tag_def` ON ((ct_tag_id=ctd_id)) WHERE ct_rc_id=rc_id ) AS `ts_tags`, ores_damaging_cls.oresc_probability AS `ores_damaging_score`, ores_goodfaith_cls.oresc_probability AS `ores_goodfaith_score` FROM `recentchanges` JOIN `comment` `comment_rc_comment` ON ((comment_rc_comment.comment_id = rc_comment_id)) JOIN `actor` `actor_rc_user` ON ((actor_rc_user.actor_id = rc_actor)) LEFT JOIN `watchlist` ON (wl_user = 28859 AND (wl_title=rc_title) AND (wl_namespace=rc_namespace)) LEFT JOIN `page` ON ((rc_cur_id=page_id)) LEFT JOIN `ores_classification` `ores_damaging_cls` ON (ores_damaging_cls.oresc_model = 11 AND (ores_damaging_cls.oresc_rev=rc_this_oldid) AND ores_damaging_cls.oresc_class = 1) LEFT JOIN `ores_classification` `ores_goodfaith_cls` ON (ores_goodfaith_cls.oresc_model = 12 AND (ores_goodfaith_cls.oresc_rev=rc_this_oldid) AND ores_goodfaith_cls.oresc_class = 1) WHERE rc_bot = 0 AND ((rc_this_oldid = page_latest) OR rc_type IN (3, 142) ) AND (rc_type != 6) AND rc_patrolled = 0 AND (rc_namespace IN ('12', '120', '146', '640', '828')) AND (rc_timestamp >= '20191216180112') AND (rc_source != 'wb') AND rc_new IN (0, 1) ORDER BY rc_timestamp DESC LIMIT 500;

The explain for that is:

*************************** 1. row ***************************
           id: 1
  select_type: PRIMARY
        table: recentchanges
         type: range
possible_keys: rc_timestamp,new_name_timestamp,rc_name_type_patrolled_timestamp,rc_ns_actor,rc_actor,rc_namespace_title_timestamp,rc_this_oldid
          key: rc_timestamp
      key_len: 16
          ref: NULL
         rows: 10704405
        Extra: Using where
*************************** 2. row ***************************
           id: 1
  select_type: PRIMARY
        table: watchlist
         type: eq_ref
possible_keys: wl_user,namespace_title,wl_user_notificationtimestamp
          key: wl_user
      key_len: 265
          ref: const,wikidatawiki.recentchanges.rc_namespace,wikidatawiki.recentchanges.rc_title
         rows: 1
        Extra: 
*************************** 3. row ***************************
           id: 1
  select_type: PRIMARY
        table: actor_rc_user
         type: eq_ref
possible_keys: PRIMARY
          key: PRIMARY
      key_len: 8
          ref: wikidatawiki.recentchanges.rc_actor
         rows: 1
        Extra: 
*************************** 4. row ***************************
           id: 1
  select_type: PRIMARY
        table: page
         type: eq_ref
possible_keys: PRIMARY
          key: PRIMARY
      key_len: 4
          ref: wikidatawiki.recentchanges.rc_cur_id
         rows: 1
        Extra: Using where
*************************** 5. row ***************************
           id: 1
  select_type: PRIMARY
        table: ores_damaging_cls
         type: eq_ref
possible_keys: oresc_rev_model_class
          key: oresc_rev_model_class
      key_len: 7
          ref: wikidatawiki.recentchanges.rc_this_oldid,const,const
         rows: 1
        Extra: 
*************************** 6. row ***************************
           id: 1
  select_type: PRIMARY
        table: ores_goodfaith_cls
         type: eq_ref
possible_keys: oresc_rev_model_class
          key: oresc_rev_model_class
      key_len: 7
          ref: wikidatawiki.recentchanges.rc_this_oldid,const,const
         rows: 1
        Extra: 
*************************** 7. row ***************************
           id: 1
  select_type: PRIMARY
        table: comment_rc_comment
         type: eq_ref
possible_keys: PRIMARY
          key: PRIMARY
      key_len: 8
          ref: wikidatawiki.recentchanges.rc_comment_id
         rows: 1
        Extra: 
*************************** 8. row ***************************
           id: 2
  select_type: DEPENDENT SUBQUERY
        table: change_tag
         type: ref
possible_keys: change_tag_rc_tag_id,change_tag_tag_id_id
          key: change_tag_rc_tag_id
      key_len: 5
          ref: wikidatawiki.recentchanges.rc_id
         rows: 1
        Extra: Using index
*************************** 9. row ***************************
           id: 2
  select_type: DEPENDENT SUBQUERY
        table: change_tag_def
         type: eq_ref
possible_keys: PRIMARY
          key: PRIMARY
      key_len: 4
          ref: wikidatawiki.change_tag.ct_tag_id
         rows: 1
        Extra: 
9 rows in set (0.00 sec)
`

I put a formatted version of the query in the comment above in P10177

P10177 (An Untitled Masterwork)

1	SELECT /* SpecialRecentChanges::doMainQuery */
2	rc_id,
3	rc_timestamp,
4	rc_namespace,
5	rc_title,
6	rc_minor,
7	rc_bot,
8	rc_new,
9	rc_cur_id,
10	rc_this_oldid,
11	rc_last_oldid,
12	rc_type,
13	rc_source,
14	rc_patrolled,
15	rc_ip,
16	rc_old_len,
17	rc_new_len,
18	rc_deleted,
19	rc_logid,
20	rc_log_type,
21	rc_log_action,
22	rc_params,
23	comment_rc_comment.comment_text AS `rc_comment_text`,
24	comment_rc_comment.comment_data AS `rc_comment_data`,
25	comment_rc_comment.comment_id AS `rc_comment_cid`,
26	actor_rc_user.actor_user AS `rc_user`,
27	actor_rc_user.actor_name AS `rc_user_text`,
28	rc_actor,
29	wl_user,
30	wl_notificationtimestamp,
31	page_latest,
32	(SELECT Group_concat(ctd_name SEPARATOR ', ')
33	FROM `change_tag`
34	JOIN `change_tag_def`
35	ON (( ct_tag_id = ctd_id ))
36	WHERE ct_rc_id = rc_id) AS `ts_tags`,
37	ores_damaging_cls.oresc_probability AS `ores_damaging_score`,
38	ores_goodfaith_cls.oresc_probability AS `ores_goodfaith_score`
39	FROM `recentchanges`
40	JOIN `comment` `comment_rc_comment`
41	ON (( comment_rc_comment.comment_id = rc_comment_id ))
42	JOIN `actor` `actor_rc_user`
43	ON (( actor_rc_user.actor_id = rc_actor ))
44	LEFT JOIN `watchlist`
45	ON ( wl_user = 28859
46	AND ( wl_title = rc_title )
47	AND ( wl_namespace = rc_namespace ) )
48	LEFT JOIN `page`
49	ON (( rc_cur_id = page_id ))
50	LEFT JOIN `ores_classification` `ores_damaging_cls`
51	ON ( ores_damaging_cls.oresc_model = 11
52	AND ( ores_damaging_cls.oresc_rev = rc_this_oldid )
53	AND ores_damaging_cls.oresc_class = 1 )
54	LEFT JOIN `ores_classification` `ores_goodfaith_cls`
55	ON ( ores_goodfaith_cls.oresc_model = 12
56	AND ( ores_goodfaith_cls.oresc_rev = rc_this_oldid )
57	AND ores_goodfaith_cls.oresc_class = 1 )
58	WHERE rc_bot = 0
59	AND ( ( rc_this_oldid = page_latest )
60	OR rc_type IN ( 3, 142 ) )
61	AND ( rc_type != 6 )
62	AND rc_patrolled = 0
63	AND ( rc_namespace IN ( '12', '120', '146', '640', '828' ) )
64	AND ( rc_timestamp >= '20191216180112' )
65	AND ( rc_source != 'wb' )
66	AND rc_new IN ( 0, 1 )
67	ORDER BY rc_timestamp DESC
68	LIMIT 500;

https://www.mediawiki.org/wiki/Manual:Hooks/ChangesListSpecialPageQuery could be useful here

Addshore moved this task from Needs Work to Needs Tech Work on the Wikidata-Campsite board.Jan 27 2020, 3:47 PM

I guess this is up to product to see if this is important enough to be tackled now that an initial tech investigation has been done!

Lydia_Pintscher moved this task from Needs Wikidata PM Work to Unconnected Stories on the Wikidata-Campsite board.May 12 2020, 12:47 PM

Umherirrender unsubscribed.Feb 27 2021, 10:16 PM

Restricted Application added a project: [DEPRECATED] wdwb-tech. · View Herald TranscriptFeb 27 2021, 10:16 PM

Umherirrender mentioned this in T276699: Loading RC on en.wikipedia with a specific set of filters throws out an exception.Mar 7 2021, 11:57 AM

Krinkle moved this task from Nov2019/1.35.wmf.5+ to Older on the Wikimedia-production-error board.Mar 10 2021, 1:42 AM

Addshore moved this task from Inbox to Legacy Inbox on the [DEPRECATED] wdwb-tech board.Mar 17 2021, 5:18 PM

Addshore moved this task from Legacy Inbox to Product Realm on the [DEPRECATED] wdwb-tech board.Apr 12 2021, 9:08 AM

MBinder_WMF added a project: Growth-Team-Filtering.Apr 15 2021, 6:51 PM

• Manuel moved this task from Unconnected Stories to Needs Wikidata PM Work on the Wikidata-Campsite board.Jun 23 2021, 9:50 AM

• Manuel updated the task description. (Show Details)Nov 25 2021, 3:11 PM

• Manuel updated the task description. (Show Details)Nov 25 2021, 3:23 PM

• Manuel updated the task description. (Show Details)Nov 25 2021, 3:56 PM

Ladsgroup mentioned this in T298847: Access to Watchlist in Wikidata returns a Fatal exception of type "Wikimedia\Rdbms\DBQueryError" (due to too many objects?).Jan 10 2022, 8:36 AM

Recentchanges table in wikidata is growing to a problematic degree. It's not wb_terms level problematic but it's quite big.

This table is the denomarlization table in mediawiki, so I don't think we should normalize it but we can look at other options, mostly improving the size horizontally instead of vertically:

Reduce max age for rc table in wikidata to 20 days or two weeks
Split it to two tables: "recentchanges" and "recentchanges_bots". While still a lot of edits bot in wikidata are not marked as bot but this still would help a lot.
Prepend all of indexes with rc_bot and make sure all queries set the rc_bot. This is a trick explained in depth in High Performance MySQL book. Basically saying if you have the field that you know is being set in all queries, while it might not have great cardinality, it's still better to put it first.
- Possibly we can just add all the new indexes for wikidata but keep it in mind rc table already has ten indexes.

Wonder what people think her.

M2k_dewiki subscribed.Jan 10 2022, 1:01 PM

Umherirrender edited projects, added Wikimedia-Slow-DB-Query; removed Performance Issue.Apr 13 2022, 6:46 PM

Ladsgroup mentioned this in T307328: Scalability issues of recentchanges table.May 2 2022, 4:43 AM

There are still some timeouts and we are trying to work on it via T307328: Scalability issues of recentchanges table. The new task supersedes this task, so I am closing this one.

Ladsgroup mentioned this in T311360: RecentChanges timing out.Jul 7 2022, 9:35 PM

WMFTimeoutException in Wikidata recentchangesClosed, DeclinedPublicPRODUCTION ERRORActions