ReleaseNotes

Dear Users,

3.13.0-rc1 (release candidate) is officially out!

Featuring:

 - uRaft HA
 - fixes to EC handling
 - nfs-ganesha plugin changed to use only C code
 - reduced number of secondary groups retrievals
 - add fuse3 client
 - many fixes


Detailed info:

* uRaft HA *

uRaft is HA solution designed for use with LizardFS. It allows for seamless switching
of master server in case of hardware failure. More information about uRaft is available
in LizardfFS Handbook (https://dev.lizardfs.com/docs/index.html)

* fixes to EC handling *

For chunk types with number of parity grater than 4 there could occur situation when
it wasn't possible to recover missing data. This was low probability event but nonetheless
it could happen. To solve this problem we have to recompute parity parts for those types of chunks.
Unfortunately until all parity parts are recomputed affected chunks are in endangered state.

* nfs-ganesha plugin changed to use only C code *

In preparation for moving LizardFS nfs-ganesha plugin to official nfs-ganesha repository,
we had to remove all occurrences of C++ code and replace it with plain C.

* reduced number of secondary groups retrievals *

In LizardFS we introduced handling of secondary groups. Unfortunately the function to retrieve
secondary groups in FUSE library turned out to be using a lot of CPU resources. Thanks to removing
unnecessary calls to this function, mount performance increased significantly.

* add fuse3 client *

LizardFS now include mount3 client which uses FUSE3 library. Thanks to new features in FUSE3,
now mount performs much better in many scenarios. Here are the most important changes visible
to LizardFS users:
 - big_writes option is now enabled by default (also it isn't recognized as a parameter anymore).
 - Added writeback_cache option. With kernel 3.14 and newer this
   enables write-back caching which can significantly improve performance.
 - increased read/write performance (specially for small operations)

Because most of the Linux distributions don't include FUSE3 library, we have build FUSE3 packages
and made them available on LizardFS page (https://lizardfs.com/)

Cheers,
Artur Kornacki
LizardFS Team