
Battle with a Phantom Postgres WAL Segment - onderkalaci
https://blog.keikooda.net/2017/10/18/battle-with-a-phantom-wal-segment/
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craigkerstiens
The follower hole was a long running bug for us back when I was at Heroku, it
existed for at least 5 years. In fact it'd become a bit of a joke so much so
that when we'd start our planning process each time
([http://www.craigkerstiens.com/2013/03/13/planning-and-
priori...](http://www.craigkerstiens.com/2013/03/13/planning-and-
prioritizing/)) we'd start by placing "fix the follower hole" in the high on
effort and low on impact to use as an anchor for everything else.

Congrats to the team for digging into a hard problem which Daniel never solved
;), squashing it, and then the great write-up about it.

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kawsper
Thanks for sharing that link, and your story about your time at Heroku, it is
very inspiring. But I have one quesiton, who is Daniel? :)

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craigkerstiens
Ha. Daniel was the first engineer hired on the Heroku Postgres team. He
authored wal-e
([https://github.com/wal-e/wal-e](https://github.com/wal-e/wal-e)) which is
the foundation for much of the fork/follower functionality and thus the
follower-hole itself. He's now running databases with me at Citus.

~~~
keiko713
and my job here at Heroku Postgres is to delete Daniel’s code

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brianwawok
Destroying is so much more work than creating.

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xtacy
Off-topic question: Does anyone know which software the authors used to create
the illustrations?

~~~
keiko713
It's a paper and pencil :P I used Ponky
([https://www.mpuni.co.jp/products/pencils/color/school/ponky/...](https://www.mpuni.co.jp/products/pencils/color/school/ponky/ponky.html))
to color and scan. After I realized that my handwriting is terrible, I
replaced several of my handwriting letters to fonts using Pixelmator ;)

