_cccc_llll_ssss_hhhh_mmmm_dddd is a daemon which facilitates the setting up and tearing down of
shared-memory communication over CrayLink between different partitions of
a partitioned Origin-2000 machine. _cccc_llll_ssss_hhhh_mmmm_dddd should not be started up
directly from the command-line. Rather, the _ssss_tttt_aaaa_rrrr_tttt_uuuu_pppp function of
_cccc_llll_ssss_hhhh_mmmm_cccc_tttt_llll(1m) should be used to set up this daemon.
Each partition of a partitioned Origin-2000 runs a distinct kernel.
CrayLink Shared-Memory allows low-latency shared-memory communication
between applications running on the distinct partitions. For such
communication to be effected, physical memory from one partition is
mapped to user buffers in a different partition. The different kernels
which are involved in such mappings have to exchange information for the
mapping to take place. _cccc_llll_ssss_hhhh_mmmm_dddd allows the kernels to communicate over
CrayLink using an RPC-like mechanism. It should be noted that the kernels
need to communicate only when the inter-partition-mapped buffers are set
up, torn down, when a new partition comes up dynamically, or when an
existing partition is brought down for administrative maintenance or
other reasons. Neither _cccc_llll_ssss_hhhh_mmmm_dddd, nor the different kernels are involved
during steady-state inter-partition shared-memory communication. The
_cccc_llll_ssss_hhhh_mmmm_dddd daemon contains some state necessary to allow the _xxxx_pppp______ffff_uuuu_nnnn_cccc(3p) user
library to have a system V-like interface which includes _pppp_aaaa_rrrr_tttt______ffff_uuuu_nnnn_cccc(3p)
helper functions. It also has a shared memory segment that is shared
between it and the clshm kernel driver. It receives messages from the
driver in this area and sends messages to the driver through _iiii_oooo_cccc_tttt_llll(2)
calls.
_cccc_llll_ssss_hhhh_mmmm_dddd takes only one parameter. This parameter is the <_uuuu_nnnn_iiii_tttt> number of
the clshm driver. This should always be """"0000"""". Other numbers are reserved
for future expansion. All other controlling state of the daemon can be
set with the different parameters of the _cccc_llll_ssss_hhhh_mmmm_cccc_tttt_llll(1m) command before the
_cccc_llll_ssss_hhhh_mmmm_cccc_tttt_llll _ssss_tttt_aaaa_rrrr_tttt_uuuu_pppp command is issued.
_cccc_llll_ssss_hhhh_mmmm_dddd uses two hwgraph files. ////hhhhwwww////ccccllllsssshhhhmmmm////0000////ccccttttllll and ////hhhhwwww////ccccllllsssshhhhmmmm////0000////sssshhhhmmmm are
used by the clshm. The """"0000"""" in the paths are the unit number of the clshm
driver. ccccttttllll stands for "control" file which is used for setting up
shared memory between the driver and daemon and the sssshhhhmmmm stands for
"shared memory" file which is used by the user library to mmap shared