Known issues for EMI WMS: http://www.eu-emi.eu/kebnekaise-products/-/asset_publisher/4BKc/content/wms

Issues and workarounds

Pending issues - no workaround yet

WMS log file location is still split between /var/log/wms and /var/log/glite. Everything should go to /var/log/glite. Supposed to be fixed in Update 11 but it's not (https://savannah.cern.ch/bugs/?86682; problem re-open in https://ggus.eu/ws/ticket_info.php?ticket=80065). The gservices-wms-admintools RPM will have to be updated with the new path when the log location changes, log rotation to be checked as well (altlogrotate component + yaim-generated entries in logrotate.d).

Critical security information is missing from /var/log/messages -- https://ggus.eu/tech/ticket_show.php?ticket=79938. Ticket open by security team. If this is fixed, then we probably don't need TSM archiving of log files as critical information will be collected by the security team via rsyslog.

WMS does not support Argus yet as the central authorization service -- expected for EMI2 (https://savannah.cern.ch/task/?func=detailitem&item_id=23030 and https://savannah.cern.ch/bugs/?90760)

WMS does not report correctly job exit code -- potentially affects Atlas software installation -- https://ggus.eu/ws/ticket_info.php?ticket=79932

Alarm on LB mysql database size not functional -- https://cern.service-now.com/service-portal/view-incident.do?n=INC111804 -- re-enable in wms_lemon.tpl when fixed or workaround found.

ICE deadlocks cause ICE job submission to stop, ICE must be restarted -- https://ggus.eu/tech/ticket_show.php?ticket=81161 Recovery procedure in WmsOperationsAndTroubleshooting.

WMS LogMonitor inefficiency - old jobs block progress on new jobs -- https://ggus.eu/tech/ticket_show.php?ticket=82586

Known EMI-1 issues and already implemented workarounds

LB fills /tmp with sockets -- https://ggus.eu/ws/ticket_info.php?ticket=80343

Fixed in EMI2: https://savannah.cern.ch/bugs/?92708

As a workaround we have a Lemon actuator restarting glite-lb-locallogger when there are more than 1500 sockets in /tmp, cf. exception 30120 (dglogd_high) in prod/cluster/gridwms/wms_lemon. This deletes all dglogd sockets in /tmp.

LB fill /var/tmp with RTM notification files -- https://ggus.eu/ws/ticket_info.php?ticket=80341

RTM monitoring causes bloat in /var/tmp when slow, causes LB notification agent to use a lot of memory and eventually crash (at around 400 notif files, 10 MB each =~ 4GB)

This is now monitored by Lemon (metric 5430 and exception 30253 in template wms_lemon) with automated recovery at 200 files and considering WMS node unhealthy ( wms_refuse_new_job exception) at 300. See also recovery procedure in WmsOperationsAndTroubleshooting.

Nordugrid CEs crashing Condor's Gridmanager continuously -- https://ggus.eu/ws/ticket_info.php?ticket=80215

Two workarounds are set up, both addressing the same issue. The first is a mitigation, the second is a fix:

1. By default there is only one Gridmanager instance, but we tell Condor to use a separate Gridmanager instance "nordugrid_gm" for all nordugrid CEs and another instance "generic_gm" for other CEs. This way not all LCG CEs will be affected by Nordugrid crashing the Gridmanager instance.

We add a GRIDMANAGER_SELECTION_EXPR setting in /opt/condor-c/etc/condor_config via a yaim post-action for config_condor_wms (defined in glite.tpl)

Manual action in order to undo when this is fixed: remove GRIDMANAGER_SELECTION_EXPR setting from /opt/condor-c/etc/condor_config

BUT we may want to keep this even now that a fix is available, as there are regular problems with nordugrid and this will improve overall isolation at little cost. So this might be kept as final configuration, not a workaround.

2. custom RPMs built by Maarten fix the problem, but not yet included in official distribution.

~maart/public/www/wms-patch/condor-7.4.2-1.lcg.x86_64.rpm (instead of "condor","7.4.2-1")

~maart/public/www/wms-patch/glite-wms-helper-3.3.2-1.sl5.x86_64.rpm (instead of "glite-wms-helper","3.3.2-0.sl5.")

They should get replaced automatically by EMI update process deployment procedure when fixed in EMI

Cron job deletes /var/proxycache when no activity -- https://ggus.eu/ws/ticket_info.php?ticket=78295

As a workaround we touch /var/proxycache/DO_NOT_DELETE_THIS_FOLDER in the yaim post-action /opt/glite/yaim/functions/post/config_glite_wms deployed via filecopy (this post function is used for other things as well)

The file should be deleted if this gets fixed.

Condor 7.4.2 not truncating Matchlog log file

This is a known problem in condor (cf. http://comments.gmane.org/gmane.comp.distributed.condor.user/20533). The file can quickly grow to GB's.
More recent versions of condor solve the problem but it would have to be seen with the developpers what versions are actually supported (configuration files may change etc.). Version 7.4.2 is the one found in the EMI 3rd-party repository http://emisoft.web.cern.ch/emisoft/dist/EMI/1/sl5/x86_64/third-party/

As a workaround we set up a daily logrotate of the Matchlog file and keep only 1 rotated log (via ncm-altlogrotate)

Missing job to clean up LBProxy database entries -- https://ggus.eu/ws/ticket_info.php?ticket=75881

Fixed in EMI2: https://savannah.cern.ch/bugs/index.php?88630

Without this the mysql database keeps growing forever.

A cron job to run glite-lb-purge with -x option is added in glite.tpl. We must specify a value for --done otherwise all jobs in the Done state are cleaned up (while not in the "regular" LBServer cleanup = glite-lb-purge without -x)

See: http://egee.cesnet.cz/mediawiki/index.php/LB_purge_and_export_to_JP#glite-lb-purge

Note that jobs cleaned with -x are moved to the zombie_jobs table (querying their status results in "410 Gone")

LCMAPS logging problems -- https://ggus.eu/ws/ticket_info.php?ticket=80065

Several issues in this area:

1. LCMAPS is still logging excessively in /var/log/messages resulting in large messages log files. Supposed to be fixed in Update 11 but it's not (https://savannah.cern.ch/bugs/?88569)

As a workaround, in glite.tpl we use the config_glite_wms post-action to redirect LCMAPS/LCAS logging to /var/log/glite/[lcas|lcmaps]-gridftp.log and set up altlogrotate to rotate the log files (12 weekly rotations i.e. 90 days)

2. We also fix the incorrect log rotation of var/log/glite/lcmaps.log reported in the same GGUS ticket with altlogrotate

Log file generation/rotation is not compliant with grid policies -- https://ggus.eu/tech/ticket_show.php?ticket=77161

As a workaround we archive logs with TSM, see TSM configuration below. When this is improved we can adjust the TSM configuration accordingly.

But if critical security information missing from /var/log/messages (cf. https://ggus.eu/tech/ticket_show.php?ticket=79938 ) is finally included, then security team collection of the important data via syslog will allow us to stop using TSM at all.

High memory usage of in glite-wms-workload daemon -- https://ggus.eu/ws/ticket_info.php?ticket=76149

High memory usage in glite-wms-workload daemon. cf. https://savannah.cern.ch/task/?20342 : this affects WMS nodes dedicated to CMS.

WMS developpers recommended (in https://ggus.eu/ws/ticket_info.php?ticket=76149) to install the jemalloc alternative malloc() to avoid high memory usage. Without it, we end up with the workload manager filling all the memory. But tests concluded that jemalloc performs not visibly better than default malloc(). On the other hand libtcmalloc from google-perftools reduces memory usage by 50%. A google-perftools build (and dependency libunwind) for slc5/x86_64 was done by Linux support.

We install the google-perftools package and set in /etc/glite-wms/glite_wms.conf (via customized YAIM actions):

RuntimeMalloc  =  "/usr/lib64/libtcmalloc_minimal.so.0";

With tcmalloc, the workload_manager process grows to 12.5GB of "RSS" memory usage then gets stable there on CMS nodes. This is OK as we have 24GB of RAM on these nodes and other processes use no more than 5-6GB in total.

As a safeguard we use the lemon monitoring to monitor memory usage of the workload_manager daemon and restart it in case it uses >14GB of memory. For more details see WmsMonitoring.

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Topic revision: r1 - 2012-07-14 - MaartenLitmaath
 
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