Windows Subsystem For Linux Performance At The End Of 2019

One of the areas where WSL has traditionally struggled is with I/O performance. WSL2 has improved the I/O performance in acting more like a Hyper-V VM than WSL1's novel design, but even for some SQLite tests WSL2 still struggles though interestingly the WSL1/WSL2 performance can outperform Windows itself in some of these SQLite tests (perhaps due to differing fsync behavior of SQLite upstream or some fsync action not handled the same under WSL).

WSL2 can deliver better I/O performance over WSL, but there still is room for improvement.

The networking performance as measured by Microsoft's own Ethr benchmark shows a sizable hit still as well out of WSL or even Windows 10 itself compared to Ubuntu.