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This page contains a few instructions on how to use the data from the grid

On this page:

Download a single file

Before submitting to the grid, it is useful to test your scripts locally. To do it, one should locate and download a single test file. Here are the instructions on how to do it:

With xrdcp command:

xrdcp root:// /some/local/path

from US, use root:// If global redirector is not working try

Another ways of getting a file

download from specific site

Locate the file in DAS by searching for file dataset=DATASET

file dataset=/SingleMuon/Run2017H-17Nov2017-v2/MINIAOD

Choose one site (in this example T2_US_MIT), and get file PFN by executing the following commands (replace the site and file name by one you need):

pfl=`curl -ks "${site}&lfn=${lfn}&protocol=srmv2" | grep PFN | cut -d "'" -f4`

then I create a user proxy:

voms-proxy-init -voms cms

Set your UID from created proxy in /tmp/x509up_u{UID}., and then set the correct X509_USER_PROXY and copy the file:

env -i X509_USER_PROXY=/tmp/x509up_u$UID gfal-copy -n 1 $pfl "file:///`pwd`/miniAOD.root"

Localing a PFN (physical file name)

OR you can locate it physical file name

edmFileUtil -d /store/relval/CMSSW_10_6_4/RelValZMM_13/MINIAODSIM/PUpmx25ns_106X_upgrade2018_realistic_v9-v1/10000/DBE18AD9-E36D-B449-B659-A71362DAC57A.root

Submit jobs using crab

Crab operations

After submitting a job via the CRAB3ConfigurationFile, a folder PROJECTFOLDER will appear. You can see your submission process and do some operation using the crab commands. The full list of crab commands can be found here: CRAB3Commands

Here is the list of the most common commands:

  • Inspect how the submission process proceeds: crab status -d PROJECTFOLDER
    • In case of errors, use crab status --verboseErrors for details
    • To resubmit failed jobs with extra options: crab resubmit -d PROJECTFOLDER --maxmemory=4000 --maxjobruntime=360 --numcores=1 --jobids=1,2
    • To kill a project: crab kill -d PROJECTFOLDER
  • The results will appear in cat PROJECTFOLDER | grep config.Data.outLFNDirBase | awk '{print $3}' | sed -e 's/"\//\/eos\/cms\//g' | sed -e 's/\/group//g' | sed -e 's/"//g'

View jobs

To view running jobs goto, click on JOBSCMS Task Monitoring - Task View

Debug failed jobs

If some of the jobs have errors, you can rerun the job locally using the following commands:

  • Inspect job ID with crab status --long -d PROJECTFOLDER. If all jobs have errors, then look at the first few jobs. Here we rerun for --jobid=0
  • To see the job log, run crab getlog --short -d PROJECTFOLDER --jobid=0 and inspect the PROJECTFOLDER/crab.log file

To resubmit the job locally:

  • run crab preparelocal -d PROJECTFOLDER.
  • from PROJECTFOLDER/local execute 1 to run the first job, the job will be executed locally after unpacking CMSSW setup.
  • kill the process with Ctrl+C
  • run cmsRun -j FrameworkJobReport.xml to inspect the output.

To inspect memory usage (you are limited to 2GB by default), execute ps aux in a different shell.

cd JOBNAME/inputs


Before executing these lines, run export X509_USER_PROXY=/tmp/x509up_u58751

  • To get all the files uploaded by a user to the crabcache and the amount of quota (in bytes) he's using:
curl -X GET '' --key $X509_USER_PROXY --cert $X509_USER_PROXY -k
  • To get more information about one specific file (the file must be owned by the user who makes the query):
curl -X GET '' --key $X509_USER_PROXY --cert $X509_USER_PROXY -k
  • To remove a specific file (currently you can only remove your files. In the future power users should be able to remove everything):
curl -X GET '' --key $X509_USER_PROXY --cert $X509_USER_PROXY -k
  • To get the quota each user has in MegaBytes:
curl -X GET '' --key $X509_USER_PROXY --cert $X509_USER_PROXY -k

Restoring tast folders:

To get full task list execute: crab tasks

  • To restore lost folder: crab remake --task=XXX
  • To clean the cache of killed job crab purge FOLDER

Obtaining Luminosity per dataset

From crab report, the location of JSON-formatted report file is listed. Copy this file to lxplus: cp PROJECTFOLDER/results/processedLumis.json .

#setup BRIL (for the first time run pip install)
export PATH=$HOME/.local/bin:/cvmfs/$PATH
# pip install --install-option="--prefix=$HOME/.local" brilws
# get lumi from the crab submission:
brilcalc lumi -b "STABLE BEAMS" -i processedLumis.json -c /cvmfs/ -u /fb

Using DAS

Several option exists to retrieve info about a dataset, here is an example for finding AOD parent file of miniAOD file:

for f in `dasgoclient --query="parent file=/store/data/Run2017D/SingleElectron/MINIAOD/09Aug2019_UL2017-v1/50000/FD85D6D5-1095-EE44-9BDF-202A69E0F25C.root"`; do
dasgoclient --query="child file=$f" | grep AOD/09Aug2019_UL

Remove button, small The additional option --normtag /afs/ is not working for me...

Accessing grid files in condor:

To use local condor batch to analyze files located at remote sites add use_x509userproxy = true in condor jdl file and setup proxy in your run file (recommended to set the proxy path first):

export X509_USER_PROXY=${HOME}/private/.x509up_${UID}
echo YOURPASSWORD | voms-proxy-init -voms cms -rfc -out ${HOME}/private/.x509up_${UID} -valid 192:00

debug condor jobs

Full list of jobs condor_q -nobatch
To connect to a running job: condor_ssh_to_job JobId
If jobs on hold: condor_q -hold -af HoldReason

-- MichaelPitt - 2019-12-08

This topic: Sandbox > TWikiUsers > MichaelPitt > MichaelPittSandbox > CMSAnalysis > UsingGrid
Topic revision: r19 - 2020-11-19 - MichaelPitt
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