PIC User Manual

NOTE: Brackets {} in the following notes have to be removed when typing in the terminal. They are used to define variables.

Once you have your PIC account you are able to access several services.

Some of them are briefly described here:

Storage

Home directory

Once you have your PIC account you are able to access the UI's machines:

ssh {USER}@ui.pic.es

and you are you are logged in to your "home":

~{USER}

This directory is your main place for storage for software, scripts, logs, and long term data files. It is backed-up and has 10GiB of capacity.

Massive storage

Each project has (in general) a mass storage space, which hangs in the following directory /pnfs/pic.es/data/{EXPERIMENT}/

Ask for the actual path to your contact person.

Inside the directory there are two different paths corresponding to two different back-ends:

Tape

As its name suggests, the data in the tape path is stored in magnetic tapes, and is critical, such as raw data or very difficult data to obtain or to get. The size of each file is usually large, from 1-2GB to 100-200GB, due to technical reasons (they are usually iso or tar.bz2 files). Data in tapes is not very often accessed. Before accessing any file on tape, you MUST notify your contact person so they can perform a pre-stage on the files you require. You have to provide also the interval during which you need to access those files. The pre-stage operation will read all the data you requested and put them on a disk buffer. Only after that, your files will be readable (using the same path). After the specified interval has passed, the pre-staged files will be removed from the disk buffer and be no longer readable.

Disk

Disk data is usually the data being currently used by the project, and it is being very often accessed. The size of the files is not important here.

Scratch

Each user has a scratch space at the following path:

/data/{EXPERIMENT}/scratch/{USER}/

This space is thought as a volatile sandbox. If you produce results that may be important for the project, ask your contact person and they will move the data into the /pnfs storage.

Please note that all data older than 6 months may be erased at any time without prior notice.

Any location not included in the former paths is not allowed and its contents erased on sight.