[Engineering] [Wikitech-l] [Ops] Changes to SWAT deployment policies, effective Monday April 30th

Fri Apr 27 19:42:04 UTC 2018

Hi!

> The new policy asks the folks submitting patches to split up patches to
> avoid bad intermediate states ahead of time.

Thank you Tyler for the explanation! Which means this patch needs to be
split into several patches? Giving the lower limit of the patches, this
becomes kinda challenging - if this patch becomes, say, three commits,
using figures from Gergo it is possible to apply it (without blocking
whole SWAT window) only in ~27% of windows available. Given that many
people can't use every window for timezone reasons, it may become tricky.

I think we should reconsider how we do both of those things - if we're
requiring splitting the patches, the limit should be considered
differently - there's no point of performing the whole cycle of checks
after merging each component of a multi-component patch, so maybe those
should be counted differently. Though, of course, merging patches
separately probably make it slower than before. If we additionally have
limit of four - which is low even by current historic usage - I am
concerned this will lead to long wait times and a backlog of patches
which might then block other work.
-- 
Stas Malyshev
smalyshev at wikimedia.org