Hello Marc, Sunday, July 29, 2007, 9:57:13 PM, you wrote:
MB> MC <rac <at> eastlink.ca> writes: >> >> Obviously 7zip is far more CPU-intensive than anything in use with ZFS >> today. But maybe with all these processor cores coming down the road, >> a high-end compression system is just the thing for ZFS to use. MB> I am not sure you realize the scale of things here. Assuming the worst case: MB> that lzjb (default ZFS compression algorithm) performs as bad as lha in [1], MB> 7zip would compress your data only 20-30% better at the cost of being 4x-5x MB> slower ! MB> Also, in most cases, the bottleneck in data compression is the CPU, so MB> switching to 7zip would reduce the I/O throughput by about 4x. 1. it depends on a specific case - sometimes it's cpu sometimes not 2. sometimes you don't really care about cpu - you have hundreds TBs of data rarely used and then squeezing 20-30% more space is a huge benefit - especially when you only read those files once they are written -- Best regards, Robert mailto:[EMAIL PROTECTED] http://milek.blogspot.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
