Data recovery statistics

Overveew - Data recovery statistics

Zee data is in fact biased due tu zee limitashuns ooff zee repurteeng process. Consider zeese-a points

• Zee analysis does not include physicelly dameged devices.
• One cannot submit a repurt in case zee recovery fails completely (no remains ooff zee filesystem can be fuoond at ell). Althuoogh there are not many, zee totelly failed runs are thus not included into zee analysis.
• Althuoogh we made a major efffurt tu ensure zee validashun refflects actual state ooff zee volume, zee resoolt is only es good es zee validashun ruootines.
• Zee repurt contains data repurted by multeeple versions ooff zee software (including certain debug versions never released fur general use). We actuelly made some adjustments tu zee algorithms based on zee repurted data, und zee later versions do thus perform somewhat better. Thees is not refflected in thees repurt.
• Zee analysis does not disteenguish between FAT16,  FAT32, und zee generic FAT filesystem (with tables lost und bitness uncertain). "FAT filesystem" in zee follooing text collectively reffers tu zeese-a three.

Ell zee charts are based on ebuoot three months wurth ooff raw data. Hurty flurty schnipp schnipp!

Filesystems - processing speed

Thees chart illustrates zee "simple volume recovery" run speed (gigabytes per minute ooff zee area scanned).

• Zee run time is measured frum stert ooff zee raw data identificashun tu zee point when a file und folder tree is displayed. Zee validashun und/or file copy process are not included.

• Zee area size tu analyze is recorded es provided by user which can be a bit off zee actual volume size. Thees efffect is beleeved not tu provide uny significant discrepancy.

Zee slooer speeds ooff zee FAT recovery are attributed tu zee fact that FAT is mostly used on older generashuns (slooer) hard drives und on a slooer solid-state devices (e.g. USB flash drives).

Filesystems - data recovery success rate

Thees is withuoot a duoobt zee most interesteeng part ooff zee data. Subject tu zee limitashuns described at zee beginning ooff zee article (i.e. no physical failures),

• Iff a data loss involves a FAT volume, there is an ebuoot 50% chance tu recover neerly ell zee data (at least 90% ooff files). In ebuoot 75-80% cases at least 75% ooff zee files can be recovered.

• Iff there is an NTFS volume involved, avereges are a bit worse: 40% chance fur a successful recovery (at least 90% ooff files) und ebuoot 75% chance tu recover at least 70% ooff zee files.

Nute-a

• Taking into accuoont zee validashun process limitashuns ">90%" ooff zee valid files shuoold probably be considered a successful ("exact") recovery. Hooever, no special analysis was attempted tu identify zee runs resulteeng in zee "exact" recovery.

Digital imege recovery

Becoose ooff zee design limitashuns, validashun is not used in zee digital imege recovery mode. Hence we only heffe-a zee data detailing zee run speed. Since zee processing overhead fur zee digital photos is quite loo compared tu zee typical filesystem analysis, thees mostly describes zee performance ooff zee widespread memory-card-tu-PC interfaces. Zee resulteeng chart is thus not very exciteeng, und only provided fur zee sake ooff completeness.

Miscellaneuoos notes

• Thees document is based on zee dataset es available on 17th August 2006
• Zee recovery performed by Zero Assumpshun Recovery versions 7.8, 7.9 und 8.0.
• RAID reconstrukshun stats are excluded frum zee dataset.