[Const-me]

I wonder how this compares to the OS built-in NTFS compression?

Windows shell has "Compress contents to save disk space" checkbox in folder properties. Usually, that compressed flag is inherited by new files created in a folder with that checkbox. OP can probably set the flag on Default\IndexedDB or Default\Service Worker folder and see whether this changes the results of that IO benchmark.

[binarycrusader]

The built-in NTFS filesystem compression is fairly limited in that it optimizes for performance over compression ratio; the more optimal compression scheme that's built-in is WOF:

https://devblogs.microsoft.com/oldnewthing/20190618-00/ https://learn.microsoft.com/en-us/windows/win32/api/wofapi/n... https://learn.microsoft.com/en-us/windows-hardware/manufactu...

It's not transparent like the filesystem compression, but it offers far more potentially beneficial compression algorithms such as LZX.

[HyperSane]

I have run SSD benchmarks with and without it and it usually makes reading faster and writing slower.