A wish came true: NetBSD finally has a journaling file system. Simon Burge added support for WAPBL, Write Ahead Physical Block Logging file system journaling, to NetBSD-current’s main branch today.

The main purpose of a journaling file system is to avoid a time consuming file system checks after a power failure, system crash or similar problem. But it can also help to improve performance considerably depending on the design. As I was curious about WAPBL’s performance impact I ran my usual benchmark (extracting the NetBSD 4.0 source tar archives). And the result is very encouraging: FFS required 15:19 minutes to finish the benchmark without logging and only 3:24 minutes to finish it with logging. It seems that WAPBL provides similar speed improvements as soft dependencies and keeps your file system safe at the same time.

A big thank you to Wasabi Systems for donating the code and to Simon Burge and all the other developers for integrating WAPBL into NetBSD!