lsb.params parameters

Syntax

DC_HOST_DEFRAG_MAX_CONCURRENT_NUMB_JOBS=integer

Description

Specify the maximum concurrent number of Dynamic Cluster jobs that can trigger a host memory defragmentation.

This parameter allows you to manage any performance impact on regular scheduler, and controls the load on network and storage infrastructure (that is, to prevent "I/O storms").

Default

Undefined. There is no limit to the number of jobs that can trigger a host memory defragmentation.

Syntax

DC_JOB_DISPATCH_RETRY_NUM=integer

Description

Number of retries for job dispatch to the Dynamic Cluster machine. If job dispatch fails during a scheduling cycle, LSF can retry the specified number of times, then the job returns to the pending state to wait for the next LSF scheduling cycle.

For example, if the number of retries is 5, LSF may make 6 attempts to dispatch the job.

Job dispatch can fail if the Dynamic Cluster host is newly provisioned but sbatchd has not started yet.

Default

5

Syntax

DC_VM_MEMSIZE_STEP=megabytes

Description

Each VM is created with memory size that is a multiple of this number. Specify the value in MB. The memory size of the VM is rounded up from the value required by the job.

For example, if a job requires 500 MB memory, and this parameter is set to 512, the VM is created with 512 MB memory. If a job requires 600 MB memory, a VM is created with 1024 MB memory.

Using this feature helps prevent the hypervisor hosts from being fragmented with multiple VMs of different size. When the VMs have standardized memory size, they can easily be reused for jobs with similar memory requirements.

The minimum memory size for a new VM is DC_VMJOB_MEM_REQ. If DC_VMJOB_MEM_REQ is not set, the minimum memory size for a new VM is hard-coded to 1024MB, even if the step size is smaller.

Dependency

Dynamic Cluster only.

This parameter is ignored if DC_VM_MEMSIZE_DEFINED is defined in dc_conf.cluster_name.xml.

Default

1024

Syntax

DC_VMJOB_MEM_REQ=megabytes

Description

Default memory requirement for a VM job. Specify the value in MB. This default is used for VM jobs that do not have any memory requirement defined at the job, queue, or application level.

A VM job must have a memory requirement because it affects the minimum memory size of the VM.

Dependency

Dynamic Cluster only.

This parameter works with DC_VM_MEMSIZE_DEFINED in dc_conf.cluster_name.xml or DC_VM_MEMSIZE_STEP in lsb.params. For example, if this parameter defines the memory requirement as 2000 MB, and the nearest allowed VM memory size is 2048, then the VM created for the job has 2048 MB memory.

Valid Values

512 minimum.

Default

1024