The VPP
home disks are NFS mounted on covpp and ~/vpphome in
your covpp home directory is a symbolic link to your vpp
home directory. Note that the VPP cannot access the rest of your
covpp home directory; you must transfer files to
~/vpphome before using them on vpp. Small files can
transferred by cp on covpp, large files should be
ftp'ed across (much faster).
Short term extra file space is available under /short on request.
Please email anusf@anu.edu.au
to request this to be set-up for your jobs.
Note that the default time that
any file can remain unused on /short
before automatic deletion is 7 days
Send mail to anusf@anu.edu.au
to request a variation of this default for your project needs. It is also
important to realise
that the files stored on /short are not backed up, hence it should
never be used as the sole store of non reproducible data or source
code.
VFL (Very Fast and Large) file systems are intended for high-speed
input and output of large amounts of data. VFL-FS is not suited (i.e.
is very inefficient) for small, frequently accessed files. Please
read the details of how to use the VFL-FS
efficiently before doing so. Note that the VFL filesystems /vflvol0
and /vflvol1 are intended for large scratch files only. It is NOT
backed up.
Two VFL file systems are available on the ANU VPP300:
/vflvol0 (on IOPE, PE0) and /vflvol1 (on IOPE PE12).
In addition /vfllocal (historically sometimes referred to as
/vflvol) will
get you to the system connected to the IOPE nearest to the PE which your job is
executing. /vflvol0 or /vflvol1 should be used in all
circumstances where you need to know where your files exist after the job has
finished or if you have a non-failsafe task to be run at the end of your job
(for example a copy over the network). The special link /vfllocal is
primarily of use for jobs that use out-of-core solvers, such as Gaussian.
It is now possible to configure a temporary memory resident filesystem
(mrfs) for the duration of your batch job. IO bandwidth to an
mrfs is the same as memory bandwidth (very fast) but size is
limited to memory size and it is a truly temporary filesystem.
Typical uses of such
a filesystem would be for TMPDIR while doing large compilations or
for Gaussian work files.
Specify the -lV size (where size is, for example,
50MB) to nqsub to reserve part of your batch memory
to be used for your batch mrfs. Note that this memory is part of
that specified in any -lM nqsub option or the per-request
memory limit default if you do not specify -lM.
Specify the -cc option to select the mrfs "directory"
as the current working directory of your batch request. This directory
will be initially empty and all its contents will be deleted at the
end of your batch request - it is the user's responsibility to
include commands in the NQS script to do any necessary copying in
and out of permanent files. Other than that, the mrfs is just
like any other filesystem but file IO will be as fast as memory
access.
Apart from using the -cc option to make the mrfs
the batch jobs current working
directory, the actual name of the directory is available through
the environment varable MRFSDIR. This variable is set by
NQS as part of initiating your job. You might notice that the mrfs
directory is located as a subdirectory of /var/spool/nqs_mrfs/ -
it is only accessible by your batch job.