3 Replies Latest reply: Sep 19, 2014 3:52 AM by Nick Dyer RSS

    Question About Compression

    Hien Dinh Newbie

      Hi All,

      Please excuse my ignorance if I don't understand how compression works with Nimble. So we have  a CS240G which is 24TB RAW and about 15.5TB usable after nimble's triple parity raid. According to the image below I'm getting 1.35X compression with about 13.56TB used and I'm already close to 90% capacity. With 1.35X compression, shouldn't I get about 20TB usuable


      nimble compression.JPG

        • Re: Question about compression
          Nick Dyer Navigator

          Hello Hien,


          The Nimble UI works on TiB (1024) rather than TB (1000) - so an array which shows 15.5TB usable is actually 17.04TB - there's an open bug to fix the terminology as it's a little confusing.


          The way we're showing data usage on your screen should be read as follows:


          Volume Usage - how much data you're actually storing on the array after any data reduction such as compression & pattern matching.

          Primary Compression - how much data space you've saved through compression so far.


          Therefore as it stands you've written a total of 19.2TiB (21.1TB) of data to the array. The array has managed to save 5.64TiB (6.2TB) of space through LZ4 compression, meaning that you are storing 13.56TiB (14.9TB) on the array itself.


          Hope this helps!