R1soft CDP - Continuous Data Protection

Continuous Data Protection — Standard Edition is Affordable High Performance Disk to Disk Backup Software for Linux Servers.  Store and Archive CDP Virtual Full Backup replicas onto any disk based storage including second hard drives, USB drives, and Network Storage (NAS).

Standard Edition's capabilities include:

• Reduce most server backup windows from hours to minutes with CDP.
• Easy Disk to Disk Backup.  Store backups on second hard drives or network storage (NAS).
• Browse and select files and folders you want excluded from CDP replication in your Data Protection Policy.
• New CDP 3 Disk Safe technology is fully portable and industrial strength.
• New CDP 3 Remote Management Web Interface
• Simultaneous Restores

Why Are Server Backups So Painful?

The reasons why backups have such a dramatic impact on server performance.

Data Sets Are Growing Rapidly

Data sets are growing rapidly and storage is always the most precious commodity a server has.  Here is a graph of hard disk capacity available as it has grown over the years.  These numbers are compiled using data available at: http://www.mattscomputertrends.com/harddiskdata.html.  If you haven't ever seen Matt's Computer Trends then you are missing out.  According to his site Matt spends his spare time scrubbing old computer magazines to find historical specs on computer components and the data he has compiled over the last few years is awesome.

Disk Performance Improvements are Not Keeping Up with Capacity Growth

Here is a graph of relative capacity of hard disks v.s. performance.  Comparing performance of hard disks is not completely straightforward so here hard disk transfer rate measured in KB/s is used.  The performance measurements are hard to come by.  The transfer rates used here are from an excellent article at Tom's Hardware that covers 15 years of hard disk performance and actually benchmarks the disks to get real performance numbers.  While the article is dated from the fall of 2006 and the fastest drive it covers is a 10,000 RPM Western Digital SATA drive the numbers don't matter much when put on a scale compared to disk capacity.  Even if we tossed in a 15,000 RPM SAS drive manufactured in 2008 it would not even be noticeable compared to the growth in capacity and the article on Tom's does a good job of driving this point home.

Here is a graph from the UCLA computer science department used in UCLA's Computer Science and Engineering (CSE 111) Introduction to Operating Systems lectures.  You can see the growth of CPU performance v.s. the hard disk. Clearly disk I/O is the most precious resource a computer has.

Backup Technology v.s. Hard Disk Capacity

This table shows the evolution of backup software technology v.s. hard disk technology.  It also shows the typical number of files found on a server.  A real challenge for typical backup software is that they have to examine every file on the server to determine if it has changed.  While this examination is done using variety of techniques discussed later the sheer volume of files that need to be indexed by the backup application is massive bottleneck.  For example imagine that unless you use R1Soft's Continuous Data Protection product you backup application probably has to walk the entire tree of file son your server.  For some servers this is not that bad.  For others you know this is very time consuming all on its own.  Factor in time to compute deltas or actually read file data and its no wonder we are only backing our servers up on a daily basis without Continuous Data Protection technology.