EXT4’s large filesystem support and performance improvements made it popular over time.
Today, EXT4 supports up to 1 Exbibyte – 260 bytes and files with sizes up to 16 tebibytes – 240 bytes. Usually, these numbers are way to high for a normal desktop or a server system. But for the worl’d largest database — Google — It makes more sense.
It all started with Ted Ts’o joining Google after finishing a two-year term as CTO of the Linux Foundation. He was the on e of the key players in the development of EXT4 file system.
Google is currently in the process of upgrading its storage infrastructure to use Ext4.
Ext4 had been controversial in the past over the data loss in the implementation of delayed allocation. Ts’o created patches that have addressed those issues, minimizing the potential risk.
In addition, the filesystem offers significant performance advantages over Ext2. In fact, EXT4 performance is very comparable to XFS, and beats it in few factors. The other adoption reason was obvious one: Smoother Upgrades
“The driving performance reason to upgrade is that while ext2 had been ‘good enough’ for a very long time the metadata arrangement on a stale file system was leading to what we call ‘read inflation’. This is where we end up doing many seeks to read one block of data. In general latency from poor block allocation was causing performance hiccups. For our workloads we saw ext4 and xfs as ‘close enough’ in performance in the areas we cared about. The fact that we had a much smoother upgrade path with ext4 clinched the deal.”
Google’s decision to deploy Ext4 is a strong endorsement of the filesystem’s reliability and affirms its suitability for enterprise adoption, this could cause a revolution and accelerated adoption throughout the industry.