On 02/26/2013 09:33 AM, Tiernan OToole wrote: > As a follow up question: Data Deduplication: The machine, to start, will > have about 5Gb RAM. I read somewhere that 20TB storage would require about > 8GB RAM, depending on block size...
The typical wisdom is that 1TB of dedup'ed data = 1GB of RAM. 5GB of RAM seems too small for a 20TB pool of dedup'ed data. Unless you know what you're doing, I'd go with just compression and let dedup be - compression has known performance and doesn't suffer with scaling. > If i dont have enough memory now, can i enable DeDupe at a later stage > when i add memory? Yes. > Also, if i pick FreeBSD now, and want to move to, say, Nexenta, is that > possible? Assuming the drives are just JBOD drives (to be confirmed) > could they just get imported? Yes, that's the whole point of open storage. I'd also recommend that you go and subscribe to z...@lists.illumos.org, since this list is going to get shut down by Oracle next month. Cheers, -- Saso _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
