Lucas_Werkmeister_WMDE added a comment.

  In T209201#4754411 <https://phabricator.wikimedia.org/T209201#4754411>, 
@Smalyshev wrote:
  
  > > One thing to consider here to stop the situation getting too terrible 
would be to add the wdqs lag to the maxlag for wikidata.org
  >
  > @Addshore I am not very informed on this one, what's maxlag and how it 
works?
  
  
  `maxlag` is a parameter that API users can specify to avoid overloading the 
wiki: if I send an API request with `maxlag=5`, and the database replicas are 
currently more than five seconds behind the master, then MediaWiki will 
immediately refuse the request. Afterwards, I’m supposed to wait for a bit 
before retrying the request. See 
https://www.mediawiki.org/wiki/Manual:Maxlag_parameter.
  
  Last year, we modified the API’s behavior so that this takes into account not 
just the replication lag, but also the dispatch lag (T194950: Include Wikibase 
dispatch lag in API "maxlag" enforcing 
<https://phabricator.wikimedia.org/T194950>) – if the database replicas are 
fine, but change dispatching to client wikis is more than 5 minutes behind, 
then requests with `maxlag=5` will still be rejected. (The 
`dispatchLagToMaxLagFactor` is configurable, 60 in production, so the threshold 
for dispatch lag should be in minutes instead of seconds if I’m not mistaken.) 
So if we can more or less easily get the (average? median? max?) query service 
update lag from within Wikibase, then it might make sense to include that lag 
in the calculation as well, with another configurable factor.
  
  As outlined in T209201#4738340 
<https://phabricator.wikimedia.org/T209201#4738340>, the implementation might 
be tricky, but I think this should in principle be doable, and would probably 
be a good idea.

TASK DETAIL
  https://phabricator.wikimedia.org/T209201

EMAIL PREFERENCES
  https://phabricator.wikimedia.org/settings/panel/emailpreferences/

To: Lucas_Werkmeister_WMDE
Cc: Lucas_Werkmeister_WMDE, Tarrow, Krenair, Addshore, TerraCodes, 
Liuxinyu970226, Aklapper, Smalyshev, alaa_wmde, Nandana, Lahi, Gq86, 
Darkminds3113, GoranSMilovanovic, QZanden, EBjune, merbst, LawExplorer, 
Vali.matei, _jensen, rosalieper, Jonas, Xmlizer, Volker_E, jkroll, 
Wikidata-bugs, Jdouglas, aude, Tobias1984, GWicke, Dinoguy1000, Manybubbles, 
Mbch331, Jay8g
_______________________________________________
Wikidata-bugs mailing list
[email protected]
https://lists.wikimedia.org/mailman/listinfo/wikidata-bugs

Reply via email to