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by sdfhbdf 1185 days ago
RO system is generally probably easier to keep up than a RW system that is constantly innovating.
1 comments

I Think he was referring to Google Search in general. I've never witness since Google went live in 1998 any Google Search downtime. Probably happened but I can not remember it.
You don't notice when their indexers cannot write; preforming a search is basically RO.
> preforming a search is basically RO

You don't know this. Google results are not the same for all users. How do you know there isn't R/W going on, particularly when signed-in to Google?

(Unless you work at Google on search, in which case I stand corrected!)

I am certain the are normally writes going on; they do run Analytics on their homepage. However they get to defer, retry and play lots of eventually consistent tricks, worst case just swallow the exceptions. The fact they can make the service _seem_ to the end user as fully working whilst being unable to write is a major factor in achieving their world beating reliability.
It is still a relatively complex multi-machine RO operation. It isn't like serving a static site.
Sure, but they can have several copies of the index per datacenter, retry your query multiple times posibly even in a diffrent datacenter. New code and even updated indexes can be tried and then fall back to yesterday's version.
Google Search is still a RO system - you are mostly just retrieving information from a search index.
It is read-online but its read systems are relatively complex and work at scale.
How do you know that?