PAR Technologies V5 manual Controlling process placement, Directory /proc/sys/ps4/local

Directory /proc/sys/ps4/local

•MaxAcksPending: maximum number of pending ACK messages until an "urgent" ACK messages will be sent.

•MaxDevSendQSize: maximum number of entries of the (protocol internal) send queue to the network device.

•MaxMTU: maximum packet size used for network packets. For sending packets, the minimum of MaxMTU and service specific MTU will be used.

•MaxRecvQSize: size of the protocol internal receive queue.

•MaxResend: Number of retries until a connection is declared as dead.

•MaxSendQSize: size of the protocol internal send queue.

•ResendTimeout: delay in "jiffies" for resending packets not acknowledged up to now. Must be greater then AckDelay.

5.2.3.Directory /proc/sys/ps4/local

Currently, there are no entries defined for this directory.

5.2.4.p4stat

The command p4stat can be used to list open sockets and network connections of the p4sock protocol.

$ /opt/parastation/bin/p4stat -s
Socket #0 : Addr: <00><00><00><00><00><'........' last_idx 0			refs 2
Socket	#1	: Addr: <70><6f><72><74><33><'port384.' last_idx 0	refs	10
Socket	#2	: Addr: <70><6f><72><74><31><'port144.' last_idx 0	refs	10

$ /opt/parastation/bin/p4stat -n
net_idx	SSeqNo SWindow RSeqNo RWindow lusridx lnetidx rnetidx snq rnq refs
84	30107	30467	30109	30468	84	84	230	0	0	2
85	30106	30466	30106	30465	85	85	231	0	0	2
86	30107	30467	30109	30468	86	86	84	0	0	2
87	30106	30466	30106	30465	87	87	85	0	0	2
88	30107	30467	30109	30468	88	88	217	0	0	2
89	30106	30466	30106	30465	89	89	218	0	0	2
90	30106	30466	30106	30465	90	90	220	0	0	2
91	30106	30466	30106	30465	91	91	221	0	0	2
92	30001	30361	30003	30362	92	92	232	0	0	2
93	30001	30361	30003	30362	93	93	219	0	0	2
94	30000	30000	30001	30360	94	94	233	0	0	2
95	30000	30000	30001	30360	95	95	222	0	0	2
96	30000	30000	30001	30360	96	96	222	0	0	2

This command shows some protocol internal parameters, like open connections, sequence numbers, reference counters, etc. For more information, see p4stat(8).

5.3. Controlling process placement

ParaStation includes sophisticated functions to control the process placement for newly created parallel and serial tasks. These processes typically require a dedicated CPU (core). Upon task startup, the environment variables PSI_NODES, PSI_HOSTS and PSI_HOSTFILE are looked up (in this order) to get

ParaStation5 Administrator's Guide 19