On 3/15/16 10:13 AM, Sven Hartge wrote:
I don't have a script, but I can provide some numbers. I did a test with a server for about 10.000 users and 2TB worth of mail, converting from Maildir++ to mdbox with zlib (level = 6) and had a final size of 1TB, so 2:1 reduction.
These numbers roughly match my results. About 6 TB of mail compresses down to about 3 TB.
The difference in ongoing CPU use for compression "on the fly" of newly arriving mail, and decompression of mail from the disk, is unnoticeable on my servers.
Also keep in mind that even if it does increase CPU usage, it reduces disk usage. This is probably an excellent tradeoff for most people, since most servers are limited by disk throughput/latency more than CPU power.
-- Robert L Mathews, Tiger Technologies, http://www.tigertech.net/