Am 27.08.2012 22:55, schrieb Adam Tauno Williams:
On Mon, 2012-08-27 at 14:32 -0400, Brian Mathis wrote:
On Mon, Aug 27, 2012 at 7:55 AM, Rainer Traut tr.ml@gmx.de wrote:
We have looked into lessfs, sdfs and ddar. Are these filesystems ready to use (on centos)? ddar is sthg different, I know.
This is something I have been thinking about peripherally for a while now. What are your impressions of SDFS (OpenDedupe)? I had been hoping it would be pretty good. Any issues with it on CentOS?
I've used it for backups; it works reliably. It is memory hungry however [sort of the nature of block-level deduplication]. http://www.wmmi.net/documents/OpenDedup.pdf
I have read the pdf and one thing strikes me: --io-chunk-size <SIZE in kB; use 4 for VMDKs, defaults to 128>
and later: ● Memory ● 2GB allocation OK for: ● 200GB@4KB chunks ● 6TB@128KB chunks ... 32TB of data at 128KB requires 8GB of RAM. 1TB @ 4KB equals the same 8GB.
We are using ESXi5 in a SAN environment, right now with a 2TB backup volume. You are right, 16GB of ram is still much... And why 4k chunk size for VMDKs?