FreeBSD + ZFS on a production server?

Wojciech Puchar wojtek at
Sun Jun 8 22:18:57 UTC 2008

> ZFS is herre to stay. You better get used to it. at least you could try
> to work with it before you make up an opinion. Have you -any- idea at
> all what this FS is capable off?

if you like - quick summary

1) ZFS "turns random writes into sequential writes" as they say. yes 
that's true. they just forgot to say that it then turns sequential reads 
into random reads. simple for anyone that still can use his/her brain.

2) ZFS RAID-z turns your X drives to single drive performance both on read 
and write. every normal RAID-5 implementation will give you random read 
speed of X-1 times single drive speed, while slow random write speeds (but 
still at least half of single drive). but this is advertised as a feature

3) a CPU,cache and memory bandwidth hogging "feature" of checksumming all 
blocks. thing that are already done in disk hardware. fortunately you can 
turn this off

4) write anywhere style of writing, just with large buffers it could get 
large blocks to be written at once if only large continous space are 

quite good (but not that much better than UFS) as long as your drive is 
mostly empty.

5) incredibly high memory consumption. very high CPU consumption compared 
to UFS.

More information about the freebsd-questions mailing list