Koji Uno wrote: > Hi, > > I'd just like you to know that UFS and normal ZFS are also > available in OpenSolaris for ARM.
That is good to know. > The CZFS is one of challenges for the embedded systems. > > There are many requests to remove unused functions > in the embedded system. When it is the closed embedded > system, it become more strong request. The reason is > to reduce the costs of hardware or testing. I fully understand the need for a low memory footprint version of ZFS and in particular one that doesn't support all the features: eg no RAIDZ2 no Quotas etc, no compression even, only supports limited checksums. However that doesn't, require changing the size of fundamental on disk structures like the block pointer such that they are no longer compatible with a full featured ZFS. Is disk space for the target systems really that tight that we have to squash the size of the block pointer ? The bit I'm missing about CZFS isn't the feature removal part but the part that changes on disk structures such that a "normal" ZFS can't read it anymore. In other words why is this effectively a fork of the on disk ZFS structure rather than a partially functioning smaller memory footprint ZFS with the same on disk structure. For example the cut down readonly ZFS that is in GRUB is a little like and embedded version it has tight memory constraints and doesn't need to understand all ZFS features. It does however need to be able to read a "normal" ZFS pool. The GRUB version has restrictions though, eg no gzip support. -- Darren J Moffat
