Two shared storage spaces are available on the CMAP workstations:
- /home : safe, backed-up storage space. The disk space is limited. It must contain your sensitive, non-replayable data (manuscripts, codes,...). This directory must not contain large calculation results.
- /home2 : Capacitive storage, unlimited, fast (10 Gbit/s link with the calculation machines). This storage is mainly intended to host your calculation results, data sets, ... You can ask for the creation of a personal directory /home2/users/login to the IT administrators. Warning, the data stored in this directory are not saved.
In some cases, you can also request temporary, unshared, and non-backuped storage space directly on a machine (in the form /users/login).
Some simple rules to remember:
- before running a program with a "print" in an inner loop of depth 15, try to evaluate how many times it will pass through it.
ducommand allows to know the size of the whole tree below the current directory.
du -sgives the same thing without the subdirectory details.
ls -lhallows to see the size of a file.
For those who are not too sure of themselves, it is possible to limit the size of the files you create:
- for bash : edit the file ~/.bashrc and add the line
ulimit -f 200000
- for (t)csh : edit the file ~/.cshrc and add the line
limit filesize 200000
You will not be able to create files larger than 200000 (200 MB)
- Do not hesitate to compress little used files, especially result files or r-text files which have a high compressibility rate.
- To compress 'toto' :
gzip toto=> toto.gz
To extract 'toto.gz' :
gunzip toto.gz=> toto
For large files of useless or unmanageable results, the
rmcommand is even better :)