| nfs_allow_all_signals |
Specifies that the NFS server adhere to signal handling requirements for blocked locks for the UNIX 95/98 test suites. A value of 1 turns
nfs_allow_all_signals on, and a value of 0 turns it off. The default is off (0). |
| nfs_device_specific_bufs |
Forces the NFS server to use the device-specific buffers. ATM and the SP high speed switch use special buffers for sending data out of the device.
The more efficiently the NFS server uses the memory allocations, the better it performs. If resource allocation of the buffers becomes difficult, turn off the
nfs_device_specific_bufs to diagnose the problem. A value of 1 turns it
on, and a value of 0 turns it off. The default is to use the device-specific buffers (1). |
| nfs_dynamic_retrans |
Controls dynamic retransmit packet resizing. The nfs_dynamic_retrans option allows the NFS read/write packets to respond to network or server load
problems. This option also allows the NFS client to vary the timeouts used for retransmissions, based on the response time of the network of server. The default
value is 1 (enabled). |
| nfs_gather_threshold |
Determines when the NFS server attempts to gather write requests to a file. If the size of the NFS write request is less than the value of the
nfs_gather_threshold option, the NFS server writes the data and immediately responds to the NFS client. If the size of the NFS write request is equal to or
greater than the value of this option's value, the NFS server writes the data and waits for a small amount of time before responding to the NFS client. The
write-gathering is a performance advantage for sequential writes, but can also be a slight performance disadvantage for random writes. To turn off write gather, set the
nfs_gather_threshold to any value greater than 8192. nfs_gather_threshold no longer applies to AIX Version 4.2.1 and later versions, but it remains
as a compatability interface. |
| nfs_iopace_pages |
Sets the maximum number of dirty pages that the NFS client flushes to the NFS server at one time. The default value is 0, which corresponds to 32 pages.
The AIX kernel will modify the default value, depending on write size. However, if you specify a value for nfs_iopace_pages, the kernel does not modify
that maximum. Valid values are between 1 and 65,536, inclusively.
The nfs_iopace_pages option is useful when the binder flushes large compilation images, thus causing interactive performance to suffer. Adjust the value
to achieve a balance between binder-write performance and interactive work. |
| nfs_max_connections |
Specifies the maximum number of TCP connections allowed on the NFS server. The default value is 0, which specifies that there is no maximum. One TCP
connection is used per client. If new TCP connections are requested from NFS clients and the new connection increases the total amount of connections beyond the
maximum, the existing TCP connection closes. The nfs_max_connections only applies to AIX Version 4.2.1 or later. |
| nfs_max_read_size |
Sets the maximum and preferred read size. The default size is 32,678 bytes. The maximum is 65,536 bytes and the minimum is 512 bytes. NFS clients mounting
after nfs_max_read_size is set must use its set value. You cannot use this option to change the size for existing mounts.
Using nfs_max_read_size may require you to reduce the V3 read/write sizes when the mounts cannot be manipulated directly in the clients, especially during NIM
installations on networks dropping packets with default read/write sizes of 32K. In this case, set the maximum size to a small value. |
| nfs_max_threads |
Specifies the maximum number of nfsd threads allowed on an NFS server. In AIX Version 4.3.2 and later versions, the default maximum is 3891. In some
systems with migration installs, the system administrator may need to increase the maximum. The maximum number may also be specified for the
nfsd daemon. The specified value overrides the default. Re-running the nfso command to set
nfs_max_threads overrides the previously set value. This option only applies to AIX Version 4.2.1 or later.
In AIX Version 4.2.1, the NFS server is multi-threaded. Threads are created as demand increases on the server. When the threads are idle, they exit, thus allowing
the server to adapt to the needs of the NFS clients. Assuming that NFS serving is the system's primary purpose, setting a large maximum does not detract from
overall system performance because the NFS server creates threads as needed. However, if you want to use the system for other activities, you should specify a
low value for nfs_max_threads. |
| nfs_max_write_size |
Sets the maximum and preferred write size. The default size is 32,678 bytes. The maximum is 65,536 bytes and the minimum is 512 bytes. NFS clients mounting
after nfs_max_write_size is set must use the set value. You cannot use this option to change the size for existing mounts.
Using nfs_max_write_size may require you to reduce the V3 read/write sizes when the mounts cannot be manipulated directly in the clients, especially
during NIM installations on networks dropping packets with default read/write sizes of 32K. In this case, set the maximum size to a small value. |
| nfs_repeat_messages |
Checks for duplicate NFS messages. This option is used to avoid displaying duplicate NFS messages. When set to a value of 1, all NFS messages are printed to
the screen. If set to a value of 0, duplicate messages appearing one after the other are not printed to the screen. Only the first message of such a sequence is
displayed. When a different message appears, a message will be displayed similar to:
Last NFS message repeated n times. |
| nfs_rfc1323 |
Enables the use of RFC1323 for NFS sockets. RFC1323 are TCP extensions for use in large bandwidth delay networks as described in the rfc1323. Use this option
to enable very large TCP window size negotiations between systems. If using the TCP transport between NFS client and server,
nfs_rfc1323 allows the systems to negotiate a TCP window size so that more data is allowed to be transferred between client and server. In this way,
nfs_rfc1323 increases the throughput potential between client and server. To use this option, both client and server must have TCP support, MTU discovery,
and socket buffers large enough to handle the new MTU size. |
| nfs_server_base_priority |
Specifies the base priority for nfsd processes. The default value is 0, giving nfsd processes regular floating priority.
Valid values are between 31 and 126, inclusively. The purpose of nfs_server_base_priority is to allow performance tuning of the NFS server or to allow
the system administrator to specify a reasonable value, depending on system load requirements. |
| nfs_server_clread |
Allows the NFS server to be very aggressive about reading a file. The NFS server can only respond to the specific read request from the NFS client. However,
the NFS server can read existing data in the file immediately after responding to the current read request. This action is commonly called read-ahead. The NFS
server performs read-ahead by default. Enabling the nfs_server_clread option causes the NFS server to be very aggressive when doing read-aheads for the NFS client.
The default value for this option is 1 (enabled). A value of 0 sets the normal system default for the read-ahead methods.
|
| nfs_setattr_error |
Tells the NFS server to ignore invalid setattr requests when its value is set to 1. The nfs_setattr_error is intended for certain personal
computer applications. The default value is 0. This option does not apply to AIX Version 4.2.1 and later versions. |
| nfs_socketsize |
Sets the queue size of the NFS server UDP (User Datagram Protocol) socket. The queue size is specified in number of bytes. The UDP socket is used for
receiving the NFS client requests and can be adjusted so that the NFS server is less likely to drop packets under a heavy load. The value of the
nfs_socketsize option must be less than the sb_max option, which can be manipulated by the no command.
In AIX Version 4, the socket size is changed dramatically. In this version and later versions, you no longer need to stop and restart the nfsd
daemon to implement changes to the socket's queue size. The default size is 60,000 bytes. Do not set the nfs_socketsize value to less than 60,000.
Large and/or busy servers should have values larger than 60,000 until UDP NFS traffic shows no packets dropped in netstat -s -p udp. |
| nfs_tcp_duplicate_cache_size |
Specifies the number of entries to store in the NFS server's duplicate cache for the TCP network transport. This option only applies to AIX Version 4.2.1 or
later. |
| nfs_tcp_socketsize |
Sets the queue size of the NFS server TCP (Transmission Control Protocol) socket. The queue size is specified in number of bytes. The TCP socket is used for
receiving the NFS client requests and can be adjusted so that the NFS server is less likely to drop packets under a heavy load. The value of the
nfs_tcp_socketsize option must be less than the sb_max option, which can be manipulated by the no command.
In AIX Version 4, the socket size is changed dramatically. In this version and later versions, you no longer need to stop and restart the nfsd
daemon to implement changes to the socket's queue size. The default size is 60,000 bytes. Do not set the nfs_tcp_socketsize value to less than 60,000.
Large and/or busy servers should have larger values until TCP NFS traffic shows no packets dropped in netstat -s -p tcp. |
| nfs_udp_duplicate_cache_size |
Specifies the number of entries to store in the NFS server's duplicate cache for the UDP network transport. This option only applies to AIX Version 4.2.1 or
later. |
| nfs_use_reserve_ports |
Forces the client to use reserved ports for all communication. The default is not to force that use. A value of 1 turns the nfs_use_reserve_ports
option on, while a value of 0 turns it off. |
| portcheck |
Checks whether an NFS request originated from a privileged port. The default value of 0 disables port checking by the NFS server. A value of
1 directs the NFS server to do port checking on the incoming NFS requests. |
| udpchecksum |
Performs the checksum of NFS UDP packets. The default value of 1 directs the NFS server or client to build UDP checksums for the packets that it sends to the
NFS clients or servers. A value of 0 disables the checksum on UDP packets from the NFS server or client. Use udpchecksum to check data integrity. |