Even Facebook struggles: Zuck's titanic database upgrade hits numerous legacy software bergs - The Register

Facebook has had all sorts of no fun trying to migrate from MySQL 5.6 to version 8.0.

A post from the social network’s engineering team reveals that Facebook's last MySQL upgrade – to version 5.6 – took "more than a year".

Some of the reasons for the slow rollout will sound familiar – such as continued work on legacy software, even as new infrastructure was being implemented.

Other parts of Facebook legacy code wouldn't work with MySQL 8.0, and therefore "required a deprecation and migration path forward".

APIs that were active in 5.6 would have been deprecated in 5.7 and possibly removed in 8.0, requiring us to update any application using the now-removed APIs," wrote Facebook software engineer Herman Lee and production engineering manager Pradeep Nayak.

Complicating matters further was Facebook's use of the MyRocks project, an effort that lets MySQL use RocksDB as its storage backend, and which Facebook was developing during its migration to MySQL 5.6.

Jumping from version 5.6 to 8,0 – and skipping version 5.7 – meant Facebook could not upgrade servers in place, so had to use logical dump and restore to build a new server.

For migration, Facebook hatched a plan to create secondary instances of MySQL databases, then copy data from version 5.6.

To get that done at Facebook scale, "we needed to build new software infrastructure", the post states matter-of-factly.

The tone used by the post's authors suggests the project has made steady progress, with glitches to be overcome rather than setbacks that derailed progress or left project timelines in tatters.

"Overall, the new version greatly expands on what we can do with MySQL @ Facebook," Lee and Nayak conclude.

The Telegraph was the first to report claims from an unnamed source that UKRI had pulled grant funding from Newport Wafer Fab earlier this week.

Or so the UK's National Audit Office (NAO) has said in a report that lays bare frailties and failures that are so commonplace that few tech pros are likely to be surprised.

The report said the UK has little chance of turning things around because public sector failures are so widespread and deep-rooted, with to few senior government officials armed with the experience and skills to run such schemes.

Our story, from a reader Regomised as "Andrew", takes us back to his time working for a certain telecommunications company, "still well known in the ISP/Telco hardware world," he said," but not as big as they used to be.".

The project is funded with a universal service obligation (USO) levy paid by telcos, but to date private entities engaged to build the network have been paid a fee for service and then used the network as a retail service provider