Installing and Administering LAN/9000 Software

receive buffers and UDP receive buffers. This can prevent situations

where processes consume excessive amounts of memory by requesting

large send or receive buffers ﬁlling these buffers by not reading data

from the socket or by sending large amounts of data. This feature was

added to 11.00 to solve a system hang problem.

The ndd parameters for setting buffer size limits are:

tcp_xmit_hiwater_max

tcp_recv_hiwater_max

udp_recv_hiwater_max

The default and maximum values for these parameters is 2147483647

bytes.

tcp_xmit_hiwater_max limits the send buffer size for TCP sockets or

communication endpoints speciﬁed in a SO_SNDBUF option of a

setsockopt() call or XTI_SNDBUF option in a t_optmgmt() call.

tcp_recv_hiwater_max and udp_recv_hiwater_max limit the receive

buffer size for TCP and UDP sockets or communication endpoints

speciﬁed in a SO_RCVBUF option of a setsockopt() call or XTI_RCVBUF

option in a t_optmgmt() call.

A setsockopt() call with a SO_SNDBUF or SO_RCVBUF option that

exceeds the corresponding kernel parameter value will fail and return

the errno value EINVAL.

A t_optmgmt() call with an XTI_SNDBUF or XIT_RCVBUF option that

exceeds the corresponding kernel parameter value will fail and return

the t_errno value TBADOPT.

OLAR - Online Addition and Replacement

This manual does not contain the procedures for adding and replacing

PCI cards using OLA/R. OLA/R stands for On Line Addition and

Replacement. This refers to the ability of a PCI I/O card to be replaced

(removed and/or added) to an HP-UX computer system designed to

support this feature without the need for completely shutting down, then

rebooting the system or affecting other system components.

If you want to utilize the OLAR feature that your system provides, refer

to the appropriate chapter in the Conﬁguring HP-UX for Peripherals for

HP 9000 Computers, Part Number B2355-90698, for information.