Hours

Available Hours is computed as follows:

1. First Compute Data Rate

Drate (Bytes/sec) = (Nlag * Nif * 2)/Crate

Drate = Data Rate to disk (Bytes per Second)

Nlags = Number of Lags (per correlation function)

Nifs = Number of Ifs (1, 2, 4) where 4 is for full stokes

2 = is because each sample is 2 bytes (16 bits)

Crate = Correlation Sample Rate (in seconds)

Note - Disk Rate is limited to approx. 20 Mbyte/sec.

2. Next Compute how long before Disk Space is used up

If the SCSI disk has 108 Gbytes of Storage

Available Hours = 108x10⁹/(Drate* 3600)

Note - 3600 converts seconds to hours

3. Example

2 Ifs, 3 Level, Sample rate = 64 usec, 64 Lags

Data Rate = 64*2*2/(64e-6) = 4 Mbyte/sec

Available Disk Storage = 108e9/(4e6*3600) = 7.5 Hours