3. Capacity Setting

3.1. First-Layer Storage Capacity Settings

You can allocate approximately 87GiB of capacity per compute node.

You can use 87GiB of capacity per compute node divided into 3 regions.

The table below shows how to specify the size of each area.

Area Name	option of “pjsub -–llio”	Setting range
Node temporary area	localtmp-size	0MiB～87GiB
Shared temporary area*1	sharedtmp-size	0MiB～87GiB
Cache area of second-layer storage*1	NONE*2	128MiB～89406MiB

*1 The value you specify is per node, and the available area size in the job is the configured value x the number of compute nodes.

*2 87GiB - (set value of “localtmp-size” + set value of “sharedtmp-size”)

For capacity setting, also check the note of Users Guide - Use and job execution..

3.2. Example of Capacity Setting

The following shows an example of whether the capacity can be set. If it cannot be set, an error occurs at pjsub as shown in the following example.

[ERR.] PJM 0049 pjsub Option argument is invalid. sharedtmp-size + localtmp-size must be less than or equal to 93615751168: --llio sharedtmp-size=XXX, localtmp-size=XXX.

Set value		Allocated size of the space			Set up Yes No
localtmp-size	sharedtmp-size	Node temporary area	Shared temporary area	Cache of second-layer storage
0Mi	0Mi	0MiB	0MiB	87GiB *	YES
10Gi	10Gi	10GiB	10GiB *	67GiB *	YES
87Gi	0Mi	87GiB	0MiB	128MiB *	YES
88Gi	0Mi	88GiB	0MiB	128MiB *	NO
0Mi	87Gi	0MiB	87GiB *	128MiB *	YES
0Mi	88Gi	0MiB	88GiB *	128MiB *	NO
44Gi	44Gi	44GiB	44GiB *	128MiB *	YES
45Gi	44Gi	45GiB	44GiB *	128MiB *	NO

* Available capacity is multiplied by the number of compute nodes.

3.3. LLIO stripe feature

The stripe setting produces the following effects.

• You can create files larger than the size specified in the job parameters.

• By distributing a single file across multiple first-tier storage, you can expect to increase file access bandwidth.

Areas covered include.

• Shared temporary area

• Cache area of second-layer storage

Example of writing a 4GiB file from a 4-node job with “shared temporary area”=2GiB, “stripe count”=4, “stripe size”=1GiB.

Option of “pjsub –llio”	Range	Description
stripe-count=count	1-24	Specifies the number of stripes per file when distributing files on first-layer storage.
stripe-size=size	64KiB-4194240KiB	Specifies the stripe size for distributing files on first-layer storage.