If logbias is set to latency (the default), ZFS will use pool log devices (if configured) to handle the requests at low latency. If logbias is set to throughput, ZFS will not use configured pool log devices. ZFS will instead optimize synchronous operations for global pool throughput and efficient use of resources.
Steps to reproduce: create a dataset with compression=gzip and logbias=througput debootstrap wheezy into that dataset chroot into it and open aptitude when it tries to rebuilds cache (/var/cache/ap...
Review the following considerations when using ZFS with a database product. ... zfs set logbias=throughput dbpool/index # zfs get primarycache,recordsize ...
If logbias is set to latency, ZFS uses the pool's separate log devices, if any, to handle the requests at low latency. If logbias is set to throughput, ...
ZFS Log Device Enhancements. Oracle Solaris 10 9/10 release: The following log device enhancements are available:. The logbias property – You can use this property to provide a hint to ZFS about handling synchronous requests for a specific dataset. If logbias is set to latency, ZFS uses the pool's separate log devices, if any, to handle the requests at low latency.
17.09.2009 · By setting Logbias=Throughput ZFS is able to divert writes away from the Logzillas which are then preserved for servicing low latency sensitive operations (e.g. redo log operations). A setting of Synchronous write bias : Throughput for a dataset allows synchronous writes to files in other datasets to have lower latency access to SSD log devices.
Logbias=throughput with no SLOG and small block writes will result in the most horrific fragmentation imaginable, which will penalize you both in the initial writes AND when you re read that data from metal later. Be very, very careful of optimizing the wrong thing and shooting yourself in both buttocks with a Barrett .50 cal.