.\" Automatically generated by Pandoc 2.0.6 .\" .TH "RPMEMD" "1" "2022-08-25" "PMDK - rpmemd version 1.4" "PMDK Programmer's Manual" .hy .\" SPDX-License-Identifier: BSD-3-Clause .\" Copyright 2016-2018, Intel Corporation .SH NAME .PP \f[B]rpmemd\f[] \- librpmem target node process (DEPRECATED) .SH SYNOPSIS .IP .nf \f[C] $\ rpmemd\ [\-\-help]\ [\-\-version]\ [] \f[] .fi .SH DESCRIPTION .PP The \f[B]rpmemd\f[] process is executed on target node by \f[B]librpmem\f[](7) library over \f[B]ssh\f[](1) and facilitates access to persistent memory over RDMA. The \f[B]rpmemd\f[] should not be run manually under normal conditions. .SH OPTIONS .PP Command line options overwrite the default \f[B]rpmemd\f[] configuration, the global configuration file and the user configuration file. .PP \f[C]\-V,\ \-\-version\f[] .PP Displays \f[B]rpmemd\f[] version and exits. .PP \f[C]\-h,\ \-\-help\f[] .PP Prints synopsis and list of parameters and exits. .PP \f[C]\-c,\ \-\-config\ \f[] .PP Custom configuration file location. If the custom configuration file is provided others are omitted. See \f[B]CONFIGURATION FILES\f[] section for details. .PP All options described in \f[B]CONFIGURATION FILES\f[] section are common for both the configuration file and the command line \- the equivalent of the following line in the config file: .PP \f[C]option\ =\ value\f[] .PP is .PP \f[C]\-\-option\ value\f[] .PP in the command line. .PP The following command line options: \f[B]\[en]persist\-apm\f[], \f[B]\[en]persist\-general\f[] and \f[B]\[en]use\-syslog\f[] should not be followed by any value. Presence of each of them in the command line turns on an appropriate option. See \f[B]CONFIGURATION FILES\f[] section for details. .PP \f[C]\-r,\ \-\-remove\ \f[] .PP Remove a pool described by given pool set file descriptor. It is interpreted as a path to the pool set file relative to the pool set directory. .PP \f[C]\-f,\ \-\-force\f[] .PP Ignore errors when removing a pool file using \f[B]\[en]remove\f[] option. .SH CONFIGURATION FILES .PP The \f[B]rpmemd\f[] searches for the configuration files with following priorities: .IP \[bu] 2 The global configuration file located in \f[B]/etc/rpmemd/rpmemd.conf\f[]. .IP \[bu] 2 The user configuration file located in the user home directory (\f[B]$HOME/.rpmemd.conf\f[]). .PP The \f[B]rpmemd\f[] can also read configuration from the custom configuration file provided using \f[B]\[en]config\f[] command line option. See \f[B]OPTIONS\f[] section for details. .PP The default configuration is described in the \f[B]DEFAULT CONFIGURATION\f[] section. .PP The configuration file is a plain text file. Each line of the configuration file can store only one configuration option defined as a \f[I]key=value\f[] pair. Empty lines and lines starting with \f[I]#\f[] are omitted. .PP The allowed options are: .IP \[bu] 2 \f[C]log\-file\ =\ \f[] \- log file location .IP \[bu] 2 \f[C]poolset\-dir\ =\ \f[] \- pool set files directory .IP \[bu] 2 \f[C]persist\-apm\ =\ {yes|no}\f[] \- enable \f[B]The Appliance Persistency Method\f[]. This option must be set only if the target platform has non\-allocating writes IO enabled. See \f[B]PERSISTENCY METHODS\f[] section for details. .IP \[bu] 2 \f[C]persist\-general\ =\ {yes|no}\f[] \- enable \f[B]The General Purpose Server Persistency Method\f[]. See \f[B]PERSISTENCY METHODS\f[] section for details. .IP \[bu] 2 \f[C]use\-syslog\ =\ {yes|no}\f[] \- use \f[B]syslog\f[](3) for logging messages instead of log file .IP \[bu] 2 \f[C]log\-level\ =\ \f[] \- set log level value. Accepted \f[I]\f[] values are: .RS 2 .IP \[bu] 2 \f[B]err\f[] \- error conditions .IP \[bu] 2 \f[B]warn\f[] \- warning conditions .IP \[bu] 2 \f[B]notice\f[] \- normal, but significant conditions .IP \[bu] 2 \f[B]info\f[] \- informational message .IP \[bu] 2 \f[B]debug\f[] \- debug\-level message .RE .PP The \f[B]$HOME\f[] sub\-string in the \f[I]poolset\-dir\f[] path is replaced with the current user home directory. .SH EXAMPLE .PP Example of the configuration file: .IP .nf \f[C] #\ This\ is\ an\ example\ of\ configuration\ file log\-file\ =\ $HOME/.logs/rpmemd.log poolset\-dir\ =\ $HOME/poolsets/ persist\-apm\ =\ yes persist\-general\ =\ no use\-syslog\ =\ no\ #\ Use\ log\ file\ instead\ of\ syslog log\-level\ =\ info \f[] .fi .SH DEFAULT CONFIGURATION .PP The \f[B]rpmemd\f[] default configuration is equivalent of the following configuration file: .IP .nf \f[C] log\-file\ =\ /var/log/rpmemd.log poolset\-dir\ =\ $HOME persist\-apm\ =\ no persist\-general\ =\ yes use\-syslog\ =\ yes log\-level\ =\ err \f[] .fi .SH PERSISTENCY METHODS .PP The \f[B]librpmem\f[](7) supports two methods for making data written to remote persistent memory durable. The difference between the use of the two mechanisms is based on whether \f[B]librpmem\f[](7) will make use of non\-allocating writes on the remote node. .IP \[bu] 2 \f[B]The General Purpose Server Persistency Method\f[] does not have any requirements for the platform on which the target daemon runs and can be enabled by administrator using the \f[I]persist\-general\f[] option. This method utilize \f[B]libpmem\f[](7) persistency mechanisms on remote node and requires additional communication between initiator and remote node using the in\-band connection. .IP \[bu] 2 \f[B]The Appliance Persistency Method\f[] requires non\-allocating writes enabled on the platform and can be enabled by administrator using \f[I]persist\-apm\f[] option. This method requires to issue an RDMA READ operation after the RDMA WRITE operations performed on requested chunk of memory. .PP \[lq]Non\-allocating write requests\[rq] is the Intel Integrated IO Controller mode where all incoming PCIe writes will utilize non\-allocating buffers for the write requests. Non\-allocating writes are guaranteed to bypass all of the CPU caches and force the write requests to flow directly to the Integrated Memory Controller without delay. .PP The \f[B]rpmemd\f[] dynamically choose the appropriate persistency method and the flushing to persistence primitive for GPSPM for each opened pool set name depending on available persistency methods and whether all pool set parts are stored in the persistent memory. .PP If the \f[B]Appliance Persistency Method\f[] is enabled and the pool set is stored in the persistent memory \f[B]rpmemd\f[] will use the \f[B]Appliance Persistency Method\f[]. If the pool set is NOT stored in the persistent memory it will fallback to the \f[B]General Puropose Server Persistency Method\f[] with \f[B]pmem_msync\f[](3). .PP If the \f[B]General Puropose Server Persistency Method\f[] is enabled and the pool set is stored in the persistent memory \f[B]rpmemd\f[] will use \f[B]pmem_persist\f[](3). If the pool set is NOT stored in the persistent momory it will use \f[B]pmem_msync\f[](3). .PP See \f[B]pmem_persist\f[](3) and \f[B]pmem_msync\f[](3) for more details. .SH NOTE .PP The \f[B]librpmem\f[](7) library and \f[B]rpmemd\f[] is deprecated since PMDK 1.12 release. If you are interested in a remote persistent memory support please look at new library \f[B]rpma\f[] https://github.com/pmem/rpma. .SH SEE ALSO .PP \f[B]ssh\f[](1), \f[B]pmem_msync\f[](3), \f[B]pmem_persist\f[](3), \f[B]syslog\f[](3), \f[B]libpmem\f[](7), \f[B]libpmemobj\f[](7), \f[B]librpmem\f[](7) and \f[B]\f[]