Is C faster for (instagram-style) ID generation?

Some time ago, guys from Instagram shared their approach to generating unique ids on multiple hosts in a way that guarantees (to reasonable extend) uniqueness, and doesn't require any centralized service.

Earlier this month, the build benchmarked their solution vs. UUIDs, and vs. bigserial.

I thought – whether C based code for nextid would be faster.

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explain.depesz.com changes and new stats

Some time ago I was contacted by Adam Smith – he pointed out that subquery names in “Subquery Scan" nodes were not properly anonymized.

Now, they are, which you can see in here:

While working on it, I also added (helpful?) links from node types to my blogposts about reading explain output – Explaining the unexplainable.

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Waiting for 9.6 – Add CASCADE support for CREATE EXTENSION.

On 3rd of October, Andres Freund committed patch:

Add CASCADE support for CREATE EXTENSION.
 
Without CASCADE, if an extension has an unfullfilled dependency on
another extension, CREATE EXTENSION ERRORs out with "required extension
... is not installed". That is annoying, especially when that dependency
is an implementation detail of the extension, rather than something the
extension's user can make sense of.
 
In addition to CASCADE this also includes a small set of regression
tests around CREATE EXTENSION.
 
Author: Petr Jelinek, editorialized by Michael Paquier, Andres Freund
Reviewed-By: Michael Paquier, Andres Freund, Jeff Janes
Discussion: <a class="text" href="/gitweb/?p=postgresql.git;a=object;h=557E0520">557E0520</a>.3040800@2ndquadrant.com

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Converting Logical Volume so that it’s striped

In case you're not familiar – there is a thing called LVM – it's a layer between physical disks, and filesystems, and allow certain interesting things, like extending, migrating, snapshotting and others.

At one of systems I've been dealing with, we stumbled upon specific requirement – change LV into striped. It took me a while to figure it out, so I'm writing it down, so I'll never have to research it again.

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