Transfer rate or throughput performance test. Determines the best typical read and write rates to a drive (device). File size is settable to bypass caching mechanisms. Backup performance will typically be less than these numbers if no compression is used. However, new advanced programs may use sophsticated multi-thread programming techniques or optimised drivers for IO and it is possible for these to equal, sometimes exceed TRMark. Therefore, TRMark is a good reference guide. If your backup program can do better than TRMark, there’s probably not much you can do to improve performance.