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Stop pregenerating and storing /page/definition responses
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Description

We should stop pregenerating /page/definitions responses to reduce the load on mobileapps. This should be safe to do given that the external request rate is very low and the current external vs. internal latencies are not too dissimilar.

  • Modify test/prod change-prop config to stop regenerating
  • Remove /page/definition storage from RESTBase
  • Remove the others_T_term_definitioniTACmxtqcTMuXLM4yrvjm4H9 keyspace from Cassandra

Event Timeline

Restricted Application removed a project: Patch-For-Review. · View Herald TranscriptTue, Aug 27, 5:03 PM
mobrovac claimed this task.Tue, Sep 3, 9:10 AM
mobrovac triaged this task as Normal priority.
mobrovac removed a project: serviceops.

Change 534122 had a related patch set uploaded (by Mobrovac; owner: Mobrovac):
[mediawiki/services/change-propagation/deploy@master] Do not pregenerate wiktionary definitions

https://gerrit.wikimedia.org/r/534122

mobrovac updated the task description. (Show Details)Tue, Sep 3, 9:33 AM

Gerrit 534122 and PR 1181 address the CP and RB side, respectively. When deploying, pregeneration should be stopped first and quickly followed by a RB deploy so as to minimise the impact on both MCS and data consistency.

Mmm... The two patches completely neglect the long cache max-age we're setting - both patches remove all the purging. We need to first figure out what are we going to do with it? If we still wanna long cache with purges - we need to modify the CP patch. If we wanna shorten cache and have no purges - need to change RB patch. I personally thing we should try having long varnish caching with purging and no storage to see how this approach affects real life latencies.

Change 534122 merged by Mobrovac:
[mediawiki/services/change-propagation/deploy@master] Do not pregenerate wiktionary definitions, only purge it

https://gerrit.wikimedia.org/r/534122

Mentioned in SAL (#wikimedia-operations) [2019-09-11T08:19:28Z] <mobrovac@deploy1001> Started deploy [changeprop/deploy@56a8342]: Stop pregenerating enwiktionary page/definition - T231361

Mentioned in SAL (#wikimedia-operations) [2019-09-11T08:22:13Z] <mobrovac@deploy1001> Finished deploy [changeprop/deploy@56a8342]: Stop pregenerating enwiktionary page/definition - T231361 (duration: 02m 45s)

Change 535794 had a related patch set uploaded (by Mobrovac; owner: Mobrovac):
[mediawiki/services/change-propagation/deploy@master] Config: Remove enwiktionary purging left-overs

https://gerrit.wikimedia.org/r/535794

Change 535794 merged by Mobrovac:
[mediawiki/services/change-propagation/deploy@master] Config: Remove enwiktionary purging left-overs

https://gerrit.wikimedia.org/r/535794

Mentioned in SAL (#wikimedia-operations) [2019-09-11T08:34:45Z] <mobrovac@deploy1001> Started deploy [changeprop/deploy@7a8ab89]: Stop pregenerating enwiktionary page/definition, take #2 - T231361

Mentioned in SAL (#wikimedia-operations) [2019-09-11T08:36:58Z] <mobrovac@deploy1001> Finished deploy [changeprop/deploy@7a8ab89]: Stop pregenerating enwiktionary page/definition, take #2 - T231361 (duration: 02m 13s)

Mentioned in SAL (#wikimedia-operations) [2019-09-11T09:08:32Z] <mobrovac@deploy1001> Started deploy [restbase/deploy@cf2ca76]: Stop using storage for enwiktionary definition and expose new PCS javascript endpoints - T231361 T232449

Mentioned in SAL (#wikimedia-operations) [2019-09-11T09:11:55Z] <mobrovac@deploy1001> Finished deploy [restbase/deploy@cf2ca76]: Stop using storage for enwiktionary definition and expose new PCS javascript endpoints - T231361 T232449 (duration: 03m 24s)

mobrovac updated the task description. (Show Details)Wed, Sep 11, 9:48 AM

Mentioned in SAL (#wikimedia-operations) [2019-09-11T10:57:24Z] <mobrovac> drop the wiktionary definition keyspace - T231361

mobrovac closed this task as Resolved.Wed, Sep 11, 10:59 AM
mobrovac updated the task description. (Show Details)
mobrovac removed a project: Patch-For-Review.

This has been completed.