Use the strun
command found in $E154_COM
directory:
strun -s
SOURCE RUN
where:
SOURCE = "raw" for raw data, "dst1" for DST1, etc
RUN = run number, eg 1337
After the data have been copied to staging disk, a symbolic link will
be created in your current working directory. Its name will be
r
RUN.SOURCE, eg r1337.raw
The E154 data will be all on Silo tapes, and there will be a catalog of tape number, file number, run number and data type (e.g. raw, DST, MC). You need to move the data to a disk file before using it. The command to do this is:
stagein -V
TAPENAME -q
FILENUM -FU -L32768 -s
MMM FN
where:
TAPENAME = Silo tapename, eg qc0100
FILENUM = file number on tape, eg 1
MMM = maximum disk file size in MB, eg 300
FN = your filename for referring to this data
Please note that it is -FU
and not -FF
as
in E143. You will not be able to read the data properly if you get
it wrong! There is a catalog
of tapes in the Silo with the approximate size of each file.
Data will be copied from tape to the staging disk, and a link will be set
up from FN to the disk file. This command may take some time
to execute, so it's probably a good idea to put it in background. If the
data is already on disk (eg from an earlier stagein command by you or
somebody else), no copying is needed and a link will be set up immediately.
Data will stay on disk until the staging system determines that there is
insufficient space for new requests. You should always issue the
stagein
command for every job, even though the disk files
have often stayed on disk for many days at a time.
If the actual data exceeds MMM MB in size, transfer will proceed until the limit is reached. If the disk file exists, but is smaller than your request and is not the complete tape file, it will be replaced. If the actual data is less than MMM MB in size, the unused space will be automatically released.
Since each tape contains no more than 1 GB, specifying 1000 MB should be sufficient in all cases. However, this is probably not a great idea. Not knowing how much will really be used, the staging system will dutifully find 1 GB of space even if it means purging other disk files, including files that you might want to use in the near future. You should look up in the catalog how much space is required for this run.
The filename FN may point to any disk or partition,
even one with practically no free space (eg your home directory), because
stagein
does not actually put the data there. It will
simply contruct a
symbolic link from FN to wherever the file really is
on the staging disk.
When stagein returns, you can direct the analysis program
to use FN as input.
There is/will be a command which integrates stagein
with
the analysis program.
Note that you can
This is useful when making DST, or writing out a large ntuple. Note that
the staging system may delete your file without warning when space runs
low. Do not use this space for anything you cannot afford to lose.
where:
When this command returns successfully, it will have created a link from
FN to an actual disk location. You can then simply write to
FN. If you do not use up all the reserved space,
it is not released until you say:
If you try to write more than the reserved
space and if there is indeed more space available on that physical disk,
it will continue to write. Unfortunately, the staging manager does not know
about it, and subsequent space allocation may be affected.
stageclr -V
TAPENAME -q
FILENUM stageclr
files originally
staged in by anyone-- be careful what you type.
Please do not
use the standard Unix command rm
for this purpose. The
space freed up may not be known to the staging system.
stageout -V
TAPENAME -q
FILENUM -lsl -FU -L32768 -sMMM -poutput
FN ...
TAPENAME = (arbitrary) tapename, e.g. FOO
FILENUM = (arbitrary) file number, eg 1
MMM = space to be reserved in MB, eg 300
FN = filename associated with it, e.g. BAR
stageupdc -V
TAPENAME -q
FILENUM