Tip
If you have data stored in an Amazon S3 bucket, then you can use datastores in MATLAB to directly access the data without needing any storage on the cluster. For details, see Transfer Data To Amazon S3 Buckets and Access Data Using MATLAB Datastore. You can also select the following storage options when creating your cluster.
Cluster Shared Storage
Persisted Storage. To request shared disk space that remains
after you shut down the cluster, select a disk size. The shared storage is mounted at
/shared/persisted. For details, see the table below.
Temporary Storage. The cluster shared file system based on
ephemeral storage on the cluster headnode. When the cluster starts, the temporary
storage is mounted at /shared/tmp, which is a distributed file
system of all the ephemeral block devices on the headnode instance. When the cluster
shuts down the content of /shared/tmp is removed. If the headnode
has no ephemeral storage, temporary storage is not available.
MATLAB Drive. To enable access to MATLAB Drive, you must use
a personal cluster. You can access the files in your MATLAB drive at the mounted
location /MATLAB Drive.
Amazon S3 Data. To transfer individual files from an Amazon
S3 bucket to the cluster machines, click Add Files. You can
specify S3 files only when creating your cluster and starting it for the first time.
When the cluster starts up, files are copied to /shared/imported.
See Copy Data from Amazon S3 Account to Your Cluster.
Local Machine Storage
Volume Size: To request an Amazon EBS Volume, enter a
number of GB in the box, e.g. 100. This results in a local data
volume, created on each worker machine of your cluster. The local data volume is
mounted at /mnt/localdata. Use this option when read/write
performance is critical.
EBS Snapshot ID: If you previously saved an EBS snapshot of
your data on Amazon, then enter the ID. The data is copied to the SSD volume attached
to each worker machine. If you provide a formatted snapshot, then the file system type
must be ext3, ext4, or xfs.
For ext3 and ext4, the full volume size of the
file system might not be immediately available when the instance comes online. Growing
the file system to full capacity can take up to 30 minutes after the instance is
online, depending on the size of the extN volume and the instance
type. You can access all data in the original snapshot as soon as the cluster is
online.
Ephemeral Storage: This type of storage is available only
on instance types that contain "d" in their name, for example, m5ad.24xlarge. Each
ephemeral storage device (NVMe SSD) is mounted at /mnt/localdataN,
where N goes from zero to the number of ephemeral storage devices
minus one, for example, /mnt/localdata1 corresponds to the second
ephemeral storage device.
After selecting your storage options, click Create Cluster. For details on other cluster settings, see Create a Cloud Cluster.
All worker machines have access to local and cluster shared storage. You can use these
folders for storing data generated by your jobs, and for data you want to transfer between the
cluster and your client location. See Transfer Data to or from a Cloud Center Cluster. The paths are the same for all worker machines
of the cluster. Changes to files and folders under /mnt/localdata are not
visible to other machines. Files and folders under the /shared mount point
are shared by all worker machines of your cluster. Changes made by any machine are visible to
all other machines. Each folder has different longevity, as shown in the table.
| Location | Size | Usage |
|---|---|---|
/mnt/localdata | Specified in cluster configuration | The location of the local machine storage volume. Each worker machine gets its own copy of the data. Temporary and intermediate data can also be written to this location. Deleted when cluster is stopped. The data is not retained between cluster runs. If you have specified an EBS snapshot, then the data is copied again when the cluster is started. |
/mnt/localdataN | Specified in cluster configuration | Only available and automatically enabled on instance types that contain "d"
in their name, for example, m5ad.24xlarge. This storage volume is backed by
ephemeral storage. Each ephemeral storage device (NVMe SSD) is mounted at
|
/MATLAB Drive | 5GB | Enabled when personal cluster is selected at cluster creation. A read-only file system on the worker machines. |
/shared/persisted | Specified at cluster creation | The location of the cluster shared persisted storage and MATLAB Job
Scheduler (MJS) data. This folder is shared among worker machines and is retained
between cluster runs. Save data you want to retrieve on the next start of the
cluster in folders and files under
Since the content in
Deleted when cluster is deleted. |
/shared/tmp | Varies with instance type, only available for instances with ephemeral storage (NVMe instance store) | This folder is shared among worker machines and is not retained between cluster runs. Use it to store temporary and intermediate data that must be visible or accessible from multiple worker machines. The available storage space depends on the ephemeral storage available on the selected machine instance type. Deleted when cluster is stopped. |
/shared/imported | Part of allocation for /shared/persisted. If both are available, then
/shared/tmp is used. | The location of the cluster shared Amazon S3 data. Selected Amazon S3
objects are copied to this location when cluster is first created/started. If
|
Note:
There is no file sharing between different clusters that use Cluster Shared Storage. Only machines within the same cluster have file sharing.
You create, start, stop, and delete your cloud clusters independent of your local MATLAB® session. Deleting an associated cluster object in MATLAB does not affect the cloud cluster or its persistent storage.
When a cluster times out, it shuts down and clears the contents of
/shared/tmp, /shared/imported,
/mnt/localdata, and /mnt/localdataN, but preserves
the content of /shared/persisted. If you use an automatic shutdown
setting for your cluster, ensure that you have all data you need from
/shared/tmp, /mnt/localdata and
/mnt/localdataN before this timeout occurs.
The contents of /shared/tmp are built using ephemeral
storage.
To check if /shared/imported is backed up by
/shared/persisted, or by /shared/tmp, run the
command ls -l /shared/imported, which displays its actual
location.
The S3 files upload works only if one or both of the following conditions is true:
The headnode is of an instance type that has ephemeral storage, for example, m5ad.24xlarge.
Persisted storage is enabled at cluster creation.
If neither of these conditions is satisfied, then the S3 files are not visible in the worker nodes. For example, if you have a cluster with a dedicated headnode of type m5.xlarge, which has no ephemeral storage, S3 uploads work only if persisted storage is enabled.