Filter
Top Products
CONSTELLATION ES.1 SAS PRODUCT MANUAL, REV. G 9
4.0 PERFORMANCE CHARACTERISTICS
This section provides detailed information concerning performance-related characteristics and features of Constellation ES.1 drives.
4.1 INTERNAL DRIVE CHARACTERISTICS
ST2000NM0001 ST1000NM0001 ST500NM0001
ST2000NM0021 ST1000NM0021 ST500NM0021
ST2000NM0041 ST1000NM0041 ST500NM0041
Drive capacity 2TB 1TB 500GB (formatted, rounded off value)
Read/write data heads 8 4 2
Bytes per track 1,012,608 1,012,608 1,012,608 Bytes (average, rounded off values)
Bytes per surface 250,000 250,000 250,000 MB (unformatted, rounded off value)
Tracks per surface (total) 248,600 248,600 248,600 Tracks (user accessible)
Tracks per inch 237,000 237,000 237,000 TPI (average)
Peak bits per inch 1,523,000 1,523,000 1,523,000 BPI
Areal density 324 324 324 Gb/in
2
Internal data rate 95 - 212 95 - 212 95 - 212 MB/s (variable with zone)
Disk rotation speed 7200 7200 7200 rpm
Avg rotational latency 4.16 4.16 4.16 ms
4.2 SEEK PERFORMANCE CHARACTERISTICS
See Section 11.4.1, "SAS physical interface" on page 53 and the SAS Interface Manual (part number 100293071) for additional timing
details.
4.2.1 Access time
Not including controller overhead
2
(ms)
1
1. Execution time measured from receipt of the Command to the Response.
,
Average Typical
43
3. Typical access times are measured under nominal conditions of temperature, voltage, and horizontal orientation as
measured on a representative sample of drives.
,
4. Access time = controller overhead + average seek time and applies to all data transfer commands.
Access to data = access time + latency time.
8.3 9.3 8.5 9.5
Single track Typical
3,4
0.5 0.8 0.7 1.0
Full stroke Typical
3,4
18 19 18.2 19.2
4.2.2 Format command execution time for 512-byte sectors (minutes)
2TB models 1TB models 500GB models
Maximum (with verify) 627 345 173
Maximum (without verify) 314 173 86
Execution time measured from receipt of the last byte of the Command Descriptor Block (CDB) to the request for a Status Byte Transfer to
the Initiator (excluding connect/disconnect).
When changing sector sizes, the format times shown above may need to be increased by 30 minutes.
2. Assumes no errors and no sector has been relocated.
Including controller overhead
1, 2
(ms)
Read Write Read Write