gordonwd Posted June 13, 2002 Report Share Posted June 13, 2002 What is a "typical" overall compression ratio when using Retrospect Express? A while back, a lot of products seemed to assume at least 2:1 compression (such a when they sell you a 4Gb tape but rate it as holding 8Gb compressed!). However, many of the larger files on people's hard disks these days are already in a compressed format and can't be shrunk much farther. For example, MP3, JPEG, GIF, MPEG, and ZIP files are already compressed, as well as many of .EXE files that are self-installing products or product updates. My latest backups with Backup Express to tape end up at about 1.5:1 compression. Just wondering. Doug Gordon Link to comment Share on other sites More sharing options...
Guest Posted June 14, 2002 Report Share Posted June 14, 2002 It depends on the files I guess. I have an Oracle Database on my laptop, and those files are not compressed at all (and in fact are mostly empty). I get 80-90% compression on those files, so 1Gb shrinks to 100-200Mb in the backup. For other file types the compression is pretty low, such as for MP3's etc. Paul Link to comment Share on other sites More sharing options...
IanWorthington Posted June 14, 2002 Report Share Posted June 14, 2002 For my initial backup Retrospect reports 0% compression, which I find hard to completely believe, but maybe. Backups since have ranged from 20% to 60%, probably averaging closer to 50%. This is for mainly "business" type data -- not too many jpgs, mp3s, or movies, though with a number a zips and compressed exes. Ian ... Link to comment Share on other sites More sharing options...
lv2ski Posted June 14, 2002 Report Share Posted June 14, 2002 It is 2:1 for files that can be compressed. Many files cannot be compressed or do not compress very well. www.dantz.com/knowledgebase has an article on compression. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.