xenial (5) sge_checkpoint.5.gz
NAME
checkpoint - Sun Grid Engine checkpointing environment configuration file format
DESCRIPTION
Checkpointing is a facility to save the complete status of an executing program or job and to restore and
restart from this so called checkpoint at a later point of time if the original program or job was
halted, e.g. through a system crash.
Sun Grid Engine provides various levels of checkpointing support (see sge_ckpt(1)). The checkpointing
environment described here is a means to configure the different types of checkpointing in use for your
Sun Grid Engine cluster or parts thereof. For that purpose you can define the operations which have to be
executed in initiating a checkpoint generation, a migration of a checkpoint to another host or a restart
of a checkpointed application as well as the list of queues which are eligible for a checkpointing
method.
Supporting different operating systems may easily force Sun Grid Engine to introduce operating system
dependencies for the configuration of the checkpointing configuration file and updates of the supported
operating system versions may lead to frequently changing implementation details. Please refer to the
<sge_root>/ckpt directory for more information.
Please use the -ackpt, -dckpt, -mckpt or -sckpt options to the qconf(1) command to manipulate
checkpointing environments from the command-line or use the corresponding qmon(1) dialogue for X-Windows
based interactive configuration.
Note, Sun Grid Engine allows backslashes (\) be used to escape newline (\newline) characters. The
backslash and the newline are replaced with a space (" ") character before any interpretation.
FORMAT
The format of a checkpoint file is defined as follows:
ckpt_name
The name of the checkpointing environment as defined for ckpt_name in sge_types(1). To be used in the
qsub(1) -ckpt switch or for the qconf(1) options mentioned above.
interface
The type of checkpointing to be used. Currently, the following types are valid:
hibernator
The Hibernator kernel level checkpointing is interfaced.
cpr The SGI kernel level checkpointing is used.
cray-ckpt
The Cray kernel level checkpointing is assumed.
transparent
Sun Grid Engine assumes that the jobs submitted with reference to this checkpointing interface use
a checkpointing library such as provided by the public domain package Condor.
userdefined
Sun Grid Engine assumes that the jobs submitted with reference to this checkpointing interface
perform their private checkpointing method.
application-level
Uses all of the interface commands configured in the checkpointing object like in the case of one
of the kernel level checkpointing interfaces (cpr, cray-ckpt, etc.) except for the restart_command
(see below), which is not used (even if it is configured) but the job script is invoked in case of
a restart instead.
ckpt_command
A command-line type command string to be executed by Sun Grid Engine in order to initiate a checkpoint.
migr_command
A command-line type command string to be executed by Sun Grid Engine during a migration of a
checkpointing job from one host to another.
restart_command
A command-line type command string to be executed by Sun Grid Engine when restarting a previously
checkpointed application.
clean_command
A command-line type command string to be executed by Sun Grid Engine in order to cleanup after a
checkpointed application has finished.
ckpt_dir
A file system location to which checkpoints of potentially considerable size should be stored.
ckpt_signal
A Unix signal to be sent to a job by Sun Grid Engine to initiate a checkpoint generation. The value for
this field can either be a symbolic name from the list produced by the -l option of the kill(1) command
or an integer number which must be a valid signal on the systems used for checkpointing.
when
The points of time when checkpoints are expected to be generated. Valid values for this parameter are
composed by the letters s, m, x and r and any combinations thereof without any separating character in
between. The same letters are allowed for the -c option of the qsub(1) command which will overwrite the
definitions in the used checkpointing environment. The meaning of the letters is defined as follows:
s A job is checkpointed, aborted and if possible migrated if the corresponding sge_execd(8) is shut
down on the job's machine.
m Checkpoints are generated periodically at the min_cpu_interval interval defined by the queue (see
queue_conf(5)) in which a job executes.
x A job is checkpointed, aborted and if possible migrated as soon as the job gets suspended
(manually as well as automatically).
r A job will be rescheduled (not checkpointed) when the host on which the job currently runs went
into unknown state and the time interval reschedule_unknown (see sge_conf(5)) defined in the
global/local cluster configuration will be exceeded.
RESTRICTIONS
Note, that the functionality of any checkpointing, migration or restart procedures provided by default
with the Sun Grid Engine distribution as well as the way how they are invoked in the ckpt_command,
migr_command or restart_command parameters of any default checkpointing environments should not be
changed or otherwise the functionality remains the full responsibility of the administrator configuring
the checkpointing environment. Sun Grid Engine will just invoke these procedures and evaluate their exit
status. If the procedures do not perform their tasks properly or are not invoked in a proper fashion, the
checkpointing mechanism may behave unexpectedly, Sun Grid Engine has no means to detect this.
SEE ALSO
sge_intro(1), sge_ckpt(1), sge__types(1), qconf(1), qmod(1), qsub(1), sge_execd(8).
COPYRIGHT
See sge_intro(1) for a full statement of rights and permissions.