Hitachi hard disk 0J11285 500 GB 2.5 " 8 MB 0J11285 Guía De Información
Los códigos de productos
0J11285
1
Advanced Format / Technology Brief
What is Advanced Format?
Advanced Format is a new technology for increasing hard drive capacities while maintaining
data integrity. In order to create higher capacity drives, manufacturers have begun the transition
to Advanced Format. HGST is now introducing new, high capacity drives with Advanced Format.
Advanced Format drives incorporate several changes to optimize the actual data structure on
the hard drive, including increasing the physical sector size from 512 bytes to a more efficient 4096 (4K) byte
sector size. In order to ease the transition, current Advanced Format drives provide 512-byte emulation (512e)1
at the drive interface for backward compatibility with legacy applications.
Most modern operating systems have been designed to work efficiently with Advanced Format drives. For optimum
performance, it is important to ensure that the drive is partitioned correctly and that data is written in 4K blocks by
both the operating system and the application. Recent operating systems handle this automatically. When using
Advanced Format drives in legacy environments, special tools may be required to optimize read/write performance.
data integrity. In order to create higher capacity drives, manufacturers have begun the transition
to Advanced Format. HGST is now introducing new, high capacity drives with Advanced Format.
Advanced Format drives incorporate several changes to optimize the actual data structure on
the hard drive, including increasing the physical sector size from 512 bytes to a more efficient 4096 (4K) byte
sector size. In order to ease the transition, current Advanced Format drives provide 512-byte emulation (512e)1
at the drive interface for backward compatibility with legacy applications.
Most modern operating systems have been designed to work efficiently with Advanced Format drives. For optimum
performance, it is important to ensure that the drive is partitioned correctly and that data is written in 4K blocks by
both the operating system and the application. Recent operating systems handle this automatically. When using
Advanced Format drives in legacy environments, special tools may be required to optimize read/write performance.
How Does Advanced Format Technology Work?
Historically, hard drives have stored data in 512-byte sector sizes (see Figure 1: Advanced Format Layout). In
addition to the user’s data, overhead data is written on the disk for each sector, including the error correction
code (ECC) and drive format information (Gap, Sync, Data Address Mark).
Advanced Format drives use longer sectors that contain 4096 (4K) bytes. This is the equivalent of putting eight
historical (512-byte) sectors into one new 4K
sector. This approach provides two benefits
illustrated in Figure 1. First, by optimizing
the overhead associated with each smaller
sector, the drive uses less space to store the
same amount of information resulting in a
format efficiency improvement (see blue ar-
row in Figure 1). The second benefit is that
a larger and more powerful error correc-
tion code (ECC) can be utilized, providing
better integrity of user data.
addition to the user’s data, overhead data is written on the disk for each sector, including the error correction
code (ECC) and drive format information (Gap, Sync, Data Address Mark).
Advanced Format drives use longer sectors that contain 4096 (4K) bytes. This is the equivalent of putting eight
historical (512-byte) sectors into one new 4K
sector. This approach provides two benefits
illustrated in Figure 1. First, by optimizing
the overhead associated with each smaller
sector, the drive uses less space to store the
same amount of information resulting in a
format efficiency improvement (see blue ar-
row in Figure 1). The second benefit is that
a larger and more powerful error correc-
tion code (ECC) can be utilized, providing
better integrity of user data.
How Does Advanced Format
Technology Maintain
Compatibility?
Many existing hardware and software components were designed around 512-byte sector (or block) sizes and
expect data to be sent and received in 512-byte segments. In order to maintain compatibility with these legacy
applications, the hard drive industry will provide 512-byte emulation at the drive interface. 512e hard drives will
transparently map all 512-byte logical blocks into the drive’s 4K physical sectors (see Figure 2: Software Stack).
expect data to be sent and received in 512-byte segments. In order to maintain compatibility with these legacy
applications, the hard drive industry will provide 512-byte emulation at the drive interface. 512e hard drives will
transparently map all 512-byte logical blocks into the drive’s 4K physical sectors (see Figure 2: Software Stack).
Figure 2: Software Stack (Potential
areas using 512-byte based code
Figure 1: Advanced Format Layout
1
512 byte emulation is sometimes referred to as 512e