- Hard Drive Data Recovery
- Data Recovery from RAID & Servers
- NAS Data Recovery
- Data Recovery from PCs & Laptops
- Data Recovery from Apple Macs
- Data Recovery from External/USB Hard Disk Drives
- Data Recovery – Lost/Deleted Files & Folders
- Mobile Phone Recovery
- Seagate Hard Drive Data Recovery
- Western Digital Hard Drive Data Recovery
- Toshiba Hard Drive Data Recovery
- SSD Data Recovery
- Advanced Recovery Service
- Photograph Recovery
- Sourcing Spare Parts
- Disk Manufacturers
- Tape Data Recovery
- Tape Conversion
- CCTV Camera Recovery
- Forensic Investigation
- SQL Recovery
- Unix/Linux Recovery
- About Us
- Contact Us
- Choose the Best
Hard drive defects table – P & G Lists
Defects Table – What are the PList and GList ?
The defects table in a hard disk drive consists of two lists: the PList and the GList. They contain records of all the defective (or ”bad”) sectors in the hard disk & provide in-built data error prevention measures.
Bad sectors fall into two categories; those created during the manufacturing process and those which develop when the drive is in operation. Hard drives are designed to identify and contain bad sectors by the use of two defect tables.
The P-list Table
Bad sectors encountered during post-manufacture testing are contained within a defect table known as the P-list (“permanent” or “primary” defect table). P-list sectors have no effect on drive access speed as they are automatically omitted by the drive electronics.
The G-list table
The G-list or “growth” defect table contains sectors which have become corrupted while the drive is in use. Although data operations are automatically redirected to uncorrupted sectors, the G-list table does reduce drive access speed and it may become necessary to replace the drive.