Write expectations exception

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Write expectations exception

Wikipedia Developers mailing list
|In a MediaWiki-based project I'm working on I'm getting many of these
kinds of exceptions: [DBPerformance] Expectation (writes <= 0) by
MediaWiki::main not met (actual: 8) |

|I've read up on the Database transactions article in mediawiki.org and
can see that to remove the exceptions we'd need to conform to some very
specific criteria for all our db write, which is quite a problem for
this particular project.

My question is, are these criteria ever likely to be enforced in future
MW versions, or will they always just be warnings to help guide
performance improvements?
|||


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Re: Write expectations exception

Kosta Harlan
My understanding is that eventually there will be enforcement in the WMF production environments, but I’m not sure about MediaWiki itself.

If you’re doing writes on GET requests, the job queue might be useful to you: https://www.mediawiki.org/wiki/Manual:Job_queue <https://www.mediawiki.org/wiki/Manual:Job_queue>

Kosta

> On Jun 17, 2019, at 8:29 AM, Aran via Wikitech-l <[hidden email]> wrote:
>
> |In a MediaWiki-based project I'm working on I'm getting many of these
> kinds of exceptions: [DBPerformance] Expectation (writes <= 0) by
> MediaWiki::main not met (actual: 8) |
>
> |I've read up on the Database transactions article in mediawiki.org and
> can see that to remove the exceptions we'd need to conform to some very
> specific criteria for all our db write, which is quite a problem for
> this particular project.
>
> My question is, are these criteria ever likely to be enforced in future
> MW versions, or will they always just be warnings to help guide
> performance improvements?
> |||
>
>
> _______________________________________________
> Wikitech-l mailing list
> [hidden email]
> https://lists.wikimedia.org/mailman/listinfo/wikitech-l

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Re: Write expectations exception

Wikipedia Developers mailing list
Hi Kosta,

I had initially not wanted to use the job queue, because it can take
minutes for jobs to execute and most of our writes need to be done
within a few seconds. But I see from that manual page that I could make
a class of jobs and a job-runner mechanism that would allow important
jobs to always get executed almost immediately, which makes the
job-queue a workable solution.

Thanks,
Aran


On 18/06/19 11:41 AM, Kosta Harlan wrote:

> My understanding is that eventually there will be enforcement in the
> WMF production environments, but I’m not sure about MediaWiki itself.
>
> If you’re doing writes on GET requests, the job queue might be useful
> to you: https://www.mediawiki.org/wiki/Manual:Job_queue
>
> Kosta
>
>> On Jun 17, 2019, at 8:29 AM, Aran via Wikitech-l
>> <[hidden email]
>> <mailto:[hidden email]>> wrote:
>>
>> |In a MediaWiki-based project I'm working on I'm getting many of these
>> kinds of exceptions: [DBPerformance] Expectation (writes <= 0) by
>> MediaWiki::main not met (actual: 8) |
>>
>> |I've read up on the Database transactions article in mediawiki.org
>> <http://mediawiki.org> and
>> can see that to remove the exceptions we'd need to conform to some very
>> specific criteria for all our db write, which is quite a problem for
>> this particular project.
>>
>> My question is, are these criteria ever likely to be enforced in future
>> MW versions, or will they always just be warnings to help guide
>> performance improvements?
>> |||
>>
>>
>> _______________________________________________
>> Wikitech-l mailing list
>> [hidden email] <mailto:[hidden email]>
>> https://lists.wikimedia.org/mailman/listinfo/wikitech-l
>

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