Storage¶
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.
- the
du
command allows to know the size of the whole tree below the current directory. du -s
gives the same thing without the subdirectory details.-
ls -lh
allows 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
rm
command is even better :)