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FAST_PATH_PORTS is a static system parameter that deactivates Fast Path for specific drivers on Alpha and Integrity servers.

FAST_PATH_PORTS is a 32-bit mask, with a bit assigned for each Fast Path port driver:

Bit value Description
1 Indicates that Fast Path is disabled for ports serviced by the corresponding driver.
0 Indicates that Fast Path is not disabled for ports serviced by the corresponding driver.

Beginning in OpenVMS Version 7.3-1, values of specific bit positions are those described in the following table:

Bit position Description
0 Controls Fast Path for PKQDRIVER (for parallel SCSI).
1 Controls Fast Path for FGEDRIVER (for Emulex LP7000, LP8000, LP9002, LP9802, LP10000 FibreChannel).
2 Controls Fast Path for PKADRIVER (for Adaptec AIC-78xx Ultra3 SCSI).
3 Controls Fast Path for PEDRIVER (for LAN).
4 Controls Fast Path for PKRDRIVER (for SMART Array 5300).
5 Controls Fast Path for PKMDRIVER, the LSI Logic LSI53C1030 SCSI port driver.
6 Controls Fast Path for PGQDRIVER, the Qlogic ISP23xx FibreChannel port driver.

Currently, the default setting for FAST_PATH_PORTS is 0, which means that Fast Path is enabled for all drivers that appear in the table.

In addition, note the following:

  • CI drivers are not controlled by FAST_PATH_PORTS. Fast Path for CI is enabled and disabled exclusively by the FAST_PATH system parameter.
  • FAST_PATH_PORTS is relevant only if the FAST_PATH system parameter is enabled (equal to 1). Setting FAST_PATH to zero has the same effect as setting all the bits in FAST_PATH_PORTS to 1.

See also