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MinutesJune16

Introduction

Minutes of the Facilities Integration Program meeting, June 16, 2010
  • Previous meetings and background : IntegrationProgram
  • Coordinates: Wednesdays, 1:00pm Eastern
    • (605) 715-4900, Access code: 735188; Dial *6 to mute/un-mute.

Attending

  • Meeting attendees: Rob, Charles, Aaron, Shawn, Sarah, Saul, Jason, Bob, Wei, John, Fred, Horst, Mark, Hiro
  • Apologies: Michael, Nate, Armen, Kaushik

Integration program update (Rob, Michael)

Special Topic: Processor Benchmarks Revisited (Bob Ball)

  • I have been mapping out the difference between the 64-bit and the 32-bit CPU2006 (HS06) benchmark on our various processors. The results are not yet complete (see below for current status) but are nonetheless interesting.
  • April 2010 64-bit Measurements, https://hep.pa.msu.edu/twiki/bin/view/AGLT2/HepSpecResults

Machine CPU(+) Speed HT on Threads RAM Speed HS06 Total HS06/core HS06 32bit Total 64bit/32bit
dc2-3-16 X5355 2.66GHz NA 8 16GB 667 64.77 8.10 59.6 1.09
sx-11-28 AMD 8220 2.80GHz NA 16 32GB 333 113.09 7.07 118.06* 0.96
bl-11-1 X5560 2.80GHz yes 6 12GB 1333 109.85 18.31 86.54* 1.27
bl-11-3 X5560 2.80GHz yes 12 12GB 1333 154.56 12.88 132.02* 1.17
bl-11-2 X5560 2.80GHz yes 16 12GB 1333 164.15 10.26 139.36* 1.18
bl-8-7 E5440 2.83GHz NA 8 16GB 667 74.15 9.27 74.07 1.00
bl-13-7 E5440 2.83GHz NA 8 16GB 667 73.65 9.21 72.56 1.02
cc-117-12 E5520 2.27GHz yes 12 24GB 1066 134.70 11.23 113.9* 1.18
bl-1-11 E5520 2.27GHz yes 8 24GB 1066 114.02 14.26 95.55 1.19
bl-1-11 E5520 2.27GHz yes 12 24GB 1066 132.64 11.05 115.17 1.15
bl-1-11 E5520 2.27GHz yes 16 24GB 1066 143.09 8.94 120.57 1.19

Note +: CPU is Intel unless noted
Note *: Using November result for similar configuration

* The question was standardization - we agreed here to use 32 mode.

Tier 3 Integration Program (Doug Benjamin & Rik Yoshida)

References
  • The link to ATLAS T3 working groups Twikis are here
  • Draft users' guide to T3g is here

last week(s):

this week:
  • No report
  • Hiro: dq2-FTS is almost complete, being tested. Available as a plug-in. Test site is ANL.

Operations overview: Production and Analysis (Kaushik)

  • this week:
    • Kaushik on vacation
    • Not much going on. Waiting on new production tasks
    • BNL jobs - large number of failures, a known problem.

Data Management & Storage Validation (Kaushik)

Shifters report (Mark)

  • Reference
  • last meeting:
    Yuri's summary from the weekly ADCoS meeting:
    http://indico.cern.ch/getFile.py/access?contribId=1&resId=0&materialId=0&confId=97636
    
    1)  BNL: Cyber-security scanning 6/9 - 6/10; no user impact is anticipated.
    2)  6/2-6/3: AGLT2 - file transfer errors - issue understood.  From Shawn:
    The network bond flapping was not the only problem. Two of our dCache pools are still rebuilding their metadata (0.92 Hz rate) and during the period the pool is reconstructing it is showing up as 100% free which gives it a very low "cost" in dCache's pool selection algorithm. 
    This caused a large number of write requests to our site to end up going to the reconstructing pool which was too busy to respond. The result was that most (all?) transfers destined for the pool failed after 600 seconds (FTS channel setting) without showing any progress in the performance markers.
    The fix was to setup the two pools as 'readonly' in the dCache admin interface to the PoolManager cell. This was done around 3 PM eastern and has resolved the problems with transfer failures for incoming files.  ggus 58720 (closed), eLog 13401.
    3)  6/3: Pilot update from Paul (v44d):
    * Rare cases of job recoveries triggered a call to panda server containing an offending parameter (‘ids’) caused problems on the server-side. Previously missed. Discovered by Tadashi Maeno.
    * Resetting of pilot option –k  (the memory requirement passed to the dispatcher when asking for a job) to default WN value causing jobs at least at LYON to run on the wrong queue (long) despite the requested minRamCount. The problem was introduced with the multi-job feature about a month ago. 
    Not discovered until yesterday. Reported by Rodney Walker.
    * Missing local/setup.sh file at ANALY_TECHNION-HEP caused jobs to fail (the PFC installation job fails because the srm looks broken). Pilot is now only using this file if it actually exists. Reported by Wensheng Deng and discussed in GGUS-ticket #58709.
    4)  6/3: From Alexei:
    ILLINOISHEP_DATADISK is added to automatic data distribution (requested by US ATLAS Operations Coordinator).
    The site successfully passed DDM FT.  eLog 13414.
    5)  6/3: AGLT2 - DDM errors, for example:
    [FTS] FTS State [Failed] FTS Retries [1] Reason [DESTINATION error during TRANSFER_PREPARATION phase: [CONNECTION_ERROR] failed to contact on remote SRM [httpg://head01.aglt2.org:8443/srm/managerv2]. Givin' up after 3tries].  From Shawn:
    The queue problem has not returned (this refers to ggus 58720). However we have an open ticket with OSG-storage about trying to resolve this type of problem: dCache: "[CONNECTION_ERROR]" from FTS to our dCac... ISSUE=8630 PROJ=71.  Once we here more we can update this ticket.  
    ggus 58772 (in progress), eLog 13428.
    6)  6/4: DDM errors at MWT2_UC_MCDISK:
    DEST SURL: srm://uct2-dc1.uchicago.edu:8443/srm/managerv2?SFN=/pnfs/uchicago.edu/atlasmcdisk/mc09_7TeV/AOD/e540_s765_s767_r1302_r1306/mc09_7TeV.108388.AlpgenQcdJ3Np3_TOPfiltjet_pt20.merge.AOD.e540_s765_s767_r1302_r1306_tid139736_00/AOD.139736._000114.pool.root.1
    ERROR MSG: [FTS] FTS State [Failed] FTS Retries [1] Reason [TRANSFER error during TRANSFER phase: [TRANSFER_TIMEOUT] gridftp_copy_wait: Connection timed out].
    >From Aaron (6/7):
    These are likely due to our firmware upgrade and then subsequent dcache service restarts. We have not seen this failure mode in a few days, so please let us know if there's still something outstanding on this ticket.  ggus 58777 (closed), eLog 13441.
    7)  6/4: IllinoisHEP - DDM errors:
    ERROR MSG: [FTS] FTS State [Failed] FTS Retries [1] Reason [DESTINATION error during TRANSFER_PREPARATION phase: [CONNECTION_ERROR] failed to contact on remote SRM [httpg://osgx1.hep.uiuc.edu:8443/srm/managerv2]. Givin' up after 3 tries].  From Dave at Illinois:
    The dCache SRM interface on osgx1.hep.uiuc.edu hung for some reason.  I have adjusted a few parameters for SRM on that node and restarted dCache.  I am now able to read/write files to that node again.  ggus 58783 (closed), eLog 13435.
    8)  6/4: BNL, DDM errors:
    ERROR MSG: [FTS] FTS State [Failed] FTS Retries [1] Reason [SOURCE error during TRANSFER_PREPARATION phase: [HTTP_TIMEOUT] failed to contact on remote SRM [httpg://dcsrm.usatlas.bnl.gov:8443/srm/managerv2]. Givin' up after 3 tries].  From Michael:
    Two factors contributed to the connection timeouts
    a) ILLINOISHEP_DATADISK was added to DDM data distribution yesterday. Last night the SE failed and caused transfer failures at a very high rate. This has blocked transfer slots in the BNL SRM server, causing other transfers having to wait for a usable slot.
    b) Load on MCDISK pools was very high for a couple of hours (has come down meanwhile) causing slow response by
    these pools.  ggus 58795 (closed), eLog 13442.
    9)  6/4: Hiro announced auto-shutoff mechanism for FTS channels with high failure rates.
    10)  6/5: AGLT2 - DDM transfers were failing with "no space left" errors:
    number of errors with following message: 799
    Error message from FTS: [FTS] FTS State [Failed] FTS Retries [1] Reason [DESTINATION error during TRANSFER_PREPARATION phase: [NO_SPACE_LEFT] No space found with at least 1484828971 bytes of unusedSize]
    >From Shawn:
    I just increased the MCDISK allocation by 45 TB.  Savannah 114953 (closed), eLog 13475.
    11)  6/5: IllinoisHEP - jobs failing with the error (from the pilot log):
    |Mover.py | !!FAILED!!3000!! Exception caught: Get function can not be called for staging input files: \'module\' object has no attribute \'isTapeSite\'.  ggus 58813 (in progress), eLog 13468.
    12)  6/5: From Bob at AGLT2:
    Analysis pilots are not coming, analysis queue is nearly drained, need to reconfigure condor slots, so I stopped further analysis pilots for about 30 minutes.  I'll restart after the re-configuration.  I just don't want new pilots ending up confused and dropped by the reconfiguration.
    Later:
    I have set us back online for ANALY_AGLT2.
    13)  6/5: MWT2_IU - jobs were failing with the error:
    Put error: lsm-put failed (201): 201 Output file does not exist | Log put error: lsm-put failed (201): 201 Output file does not exist.  From Sarah at IU:
    I ran proddisk_cleanse, and it looks like the dbrelease file is one of the files it removed. It's been re-transmitted, so this error should stop.  ggus 58814 (closed), eLog 13485.
    14)  6/8: MWT2_IU - DDM errors like:
    FTS State [Failed] FTS Retries [1] Reason [SOURCE error during TRANSFER_PREPARATION phase: [LOCALITY] Source file... locality is UNAVAILABLE].  From Sarah at IU:
    One of our pools went down this morning due to memory issues. I've restarted the pool and these transfers should start to succeed. 
    
    Follow-ups from earlier reports:
    
    (i)  4/23: OU sites were set off-line in advance of major upgrades -- from Horst:
    We'll be taking OU_OCHEP_SWT2 down for a complete hardware and software upgrade on Monday morning.  So could you please drain all the queues -- both *OU_OCHEP_* and *OU_OSCER_* -- and turn pilot submission (and everything else that might be accessing them) off starting this afternoon, 
    until we're ready to start back up, which will be at least a week?  
    I'll also schedule a maintenance in OSG OIM, which I will keep updated when we know better how long Dell and DDN will take for the upgrade.  eLog 11813.
    Update, week of 5/19-26: Horst thinks the upgrade work is almost done, so the site may be back on-line soon.
    ii)  6/2: Maintenance outage at MWT2_UC - from Aaron:
    We are taking a downtime June 2nd in order to update our networking infrastructure as well as upgrade to a new kernel on our worker nodes. We will be down from 9AM - 5PM CST, will send an announcement when we're back on-line.  (In progress.)
    Update, 6/2 p.m., from Aaron: Our downtime has finished successfully. We are now running a new firmware on our 6509, as well as a new kernel on all our worker nodes. We have run test jobs across our site and they have completed, and are in transferring state now.  We are setting our site back online.
    
  • this meeting:
    Yuri's summary from the weekly ADCoS meeting:
    http://indico.cern.ch/getFile.py/access?contribId=0&resId=0&materialId=slides&confId=98432
    
    1)  6/11: MWT2_UC DDM errors such as:
    FTS State [Failed] FTS Retries [1] Reason [SOURCE error during TRANSFER_PREPARATION phase: [HTTP_TIMEOUT] failed to contact on remote SRM [httpg://uct2-dc1.uchicago.edu:8443/srm/managerv2]. Givin' up after 3 tries]
    >From Sarah:
    It looks like PNFS failed at 12:01 AM, coinciding with the start of a pnfsDump run. SRM failed at 4 AM, due to filling memory with PNFS requests. We're still investigating the causes of the PNFS failure.  We're looking at other options, like Chimera and better hardware.  ggus 58966 (closed), eLog 13676.
    2)  6/11: From Bob at AGLT2: Had an NFS problem.  Noted too late.  Nearly all running jobs lost.  Problem now repaired, should be OK shortly.  The next day (Saturday, 6/12) there were still some stale condor jobs on the BNL submit host -  some of these were removed, 
    others eventually cleared out of the system.  eLog 13718.
    3)  6/12: Job failures at BNL - example from the pilot log:
    12 Jun 09:00:55|Mover.py | !!FAILED!!2999!! Error in copying (attempt 1): 1099 - dccp failed with output: ec = 256,
    12 Jun 09:00:55|Mover.py | !!FAILED!!2999!! Failed to transfer log.144950._567122.job.log.tgz.1: 1099 (Get error: Staging input file failed).  Issue resolved, ggus 58986 (closed), eLog 13708.
    4)  6/12: WISC - job failures with errors like:
    FTS Retries [1] Reason [DESTINATION error during TRANSFER_PREPARATION phase: [GENERAL_FAILURE] Error:/bin/mkdir: cannot create directory ...: Permission deniedRef-u xrootd /bin/mkdir.  Update 6/15 from Wen:
    The CS room network was still messed up by a power cut and the main servers are still not accessible. Now I drag out some other machines to start these services. I hope I can get the main server as soon as possible.  Savannah 115123 (open), eLog 13790.
    5)  6/13-14: Power problem at AGLT2 - from Shawn:
    The primary input circuit breaker on our APC 80kW UPS system had tripped at 4:10 AM. Apparently the last of the batteries ran out around 5:10 AM.  System breaker was reset around 1:15 PM. Still checking that all systems have come back up in an operational way.  
    Test jobs successful, site back to on-line.  
    ggus 59002 & RT 17217 (closed), eLog 13770.
    6)  6/14 - 6/16: SWT2_CPB - problem with the internal cluster switch stack.  Restored once early Monday morning, but the problem recurred after ~ 4 hours.  Working with Dell tech support to resolve the issue.  ggus 59006 & RT 17220 (open), eLog 13776.
    7)  6/15: DB Release 10.9.1 was corrupted, resulting in large numbers of failed jobs.  Updated version released.  Savannah 68831.
    8)  6/15: BNL FTS was upgraded to v2.2.4 (Hiro).
    
    Follow-ups from earlier reports:
    (i)  4/23: OU sites were set off-line in advance of major upgrades -- from Horst:
    We'll be taking OU_OCHEP_SWT2 down for a complete hardware and software upgrade on Monday morning.  So could you please drain all the queues -- both *OU_OCHEP_* and *OU_OSCER_* -- and turn pilot submission (and everything else that might be accessing them) off starting this afternoon, 
    until we're ready to start back up, which will be at least a week?  I'll also schedule a maintenance in OSG OIM, which I will keep updated when we know better how long Dell and DDN will take for the upgrade.  eLog 11813.
    Update, week of 5/19-26: Horst thinks the upgrade work is almost done, so the site may be back on-line soon.
    Update 6/10, from Horst:
    We're working on release installations now with Alessandro, and there seem to be some problems, possibly related to the fact that the OSG_APP area is on the Lustre file system.
    (ii)  6/3: AGLT2 - DDM errors, for example:
    [FTS] FTS State [Failed] FTS Retries [1] Reason [DESTINATION error during TRANSFER_PREPARATION phase: [CONNECTION_ERROR] failed to contact on remote SRM [httpg://head01.aglt2.org:8443/srm/managerv2]. Givin' up after 3tries].  From Shawn:
    The queue problem has not returned (this refers to ggus 58720). However we have an open ticket with OSG-storage about trying to resolve this type of problem: dCache: "[CONNECTION_ERROR]" from FTS to our dCac... ISSUE=8630 PROJ=71.  Once we here more we can update this ticket.  
    ggus 58772 (in progress), eLog 13428.
    Update, 6/9: No recent errors of this type seen - ggus 58772 closed.
    (iii)  6/4: Hiro announced auto-shutoff mechanism for FTS channels with high failure rates.
    Update, 6/11 (from Hiro):
    The auto-shutoff has been modified to check the source error as well.   The threshold of error rate is 150 errors per 10 minutes.  And, the following three errors are only counted in the check.
    1.  No space left error.
    2.  Destination error
    3.  failed to contact remove SRM
    The shutoff should only happen when the SE is really not working.   And, it should not casually turn off channel .
    (iv)  6/5: IllinoisHEP - jobs failing with the error (from the pilot log):
    |Mover.py | !!FAILED!!3000!! Exception caught: Get function can not be called for staging input files: \'module\' object has no attribute \'isTapeSite\'.  ggus 58813 (in progress), eLog 13468.
    

DDM Operations (Hiro)

Throughput Initiative (Shawn)

  • NetworkMonitoring
  • https://www.usatlas.bnl.gov/dq2/throughput
  • Now there is FTS logging to the DQ2 log page at: http://www.usatlas.bnl.gov/dq2log/dq2log (type in 'fts' and 'id' in the box and search).
  • last week(s):
    • NetworkMonitoring
    • Biweekly meeting yesterday. Personar issues discussed - new RH-based version coming mid-Aug. Probably won't have another Knoppix release.
    • Patch for display issues available.
    • Transaction tests and plotting - to be covered next time; alerts as well.
    • New hardware platform perfsonar - 10G capability
  • this week:
    • Minutes from meeting:
      	USATLAS Throughput Meeting Notes --- June 15, 2010
                       ==================================================
      
      Attending: John, Philippe, Jason, Sarah, Andy, Dave, Aaron, Charles, Hiro, Karthik
      Excused:
      
      1) perfSONAR status:  a) New hardware install status report about possible future perfSONAR platform.  It is in place at AGLT2 and installed with current version.  Shawn will send out details to Internet2/ESnet developers later today.   b) Comments on speed and usability of current software on KOI systems:  very problematic because system slowness makes it painful to examine results.   Jason said some effort is being made to isolate the source of the problem.   Possibly non-optimal SQL queries are the problem.   Being investigated.
      
      2) Transaction tests:   a) Nothing new yet.  Once URL with results is ready Hiro will make it available.
      
      3) perfSONAR alerting:  a) Nothing new from Shawn or Sarah,  b) update on API...Jason, will see if API fixes will make it into the next version.   Will be important to have this for future "set and forget" capability.
      
      4) Site reports:
      
         a) MWT2:  Firmware upgrade on switch/router (Cisco 6509).   Looks like it worked. Unable to cause the problem using the same test (Iperf across the backplane using two sets of src/destinations).  
         b) BNL:  Problem with poor performance a few weeks ago (which was routed around) turned out to be a bad 10GE card.  Seeing overruns incrementing on the bad card. Possible "diags schedule" command pointed out by Aaron (UC). 
         c) OU:  Still problem with throughput service going to "Not Running".   Aaron will contact Karthik to see if DB related. 
         d) Internet2/ESnet: New CentOS based perfSONAR LiveCD version maybe ready for alpha testing by mid-July.   Possibility in the future to install to disk and use YUM to update system.  Sites can choose to still run from CD.   
         e) AGLT2:  Brief report on last week's Transatlantic Networking Workshop.  URL for it: http://indico.cern.ch/conferenceTimeTable.py?confId=88883#20100611.detailed  
      
      Planning to meet again in two weeks.  
      
      Please send along corrections or additions to the mailing list.
      
      Thanks,
      
      Shawn
  • Next perfsonar release candidate expected mid-July
  • News from networking meeting - ATLAS most likely moving to a flatter data distribution model (more like CMS)

Site news and issues (all sites)

  • T1:
    • last week(s): Planning to upgrade Condor clients on worker nodes next week. Force 10 code update. Continue testing DDN.
    • this week:

  • AGLT2:
    • last week: Watching space tokens. 100 TB free. New storage nodes at MSU - 8 MD1200. Will be purchasing head nodes. Upgraded OSG wn-client 1.2.9; upgraded wlcg-client. Founding lcg-cp hangs, for up to 8 hours. 7.4 Condor; Updated dCache. Found throughput drop off last night - found traffic bouncing between bonded NICs, fixed and restarted network service. Backing up dcache metadata.
    • this week: Power issue over weekend - 80 kW Symmetra input breaker tripped, down for several hours and then recovery; resolved on Monday. 2 second interruption today covered UPS.

  • NET2:
    • last week(s): Dell storage arriving; focusing on networking. all is well, 110 TB free space; new storage still arriving;
    • this week: Will go offline for a firmware upgrade on GPFS servers. Racking and stacking storage.

  • MWT2:
    • last week(s): Analy-x queue work continues (distributed xrootd backend). Build jobs working, fixing config for LFC lookup. Cisco firmware update - testing under load.
    • this week: Updating 64 8 core nodes adding disk, doing raid0, 70% I/O improvement. Cisco all okay with heavy IO doing pool-to-pool transfers

  • SWT2 (UTA):
    • last week: Water leak in machine room - dumped power to the lab. During the downtime put in an xrootd to report usage of space token. Will be bringing 200 TB online shortly. Network update - met w/ CIO last week, now have an upgrade path. Ordered a dedicated 10G port for switch in Dallas ~ 2 months. Bid for fiber to Dallas - 3 months. (NLR in Dallas, and I2 will be bringing 10G there). Dallas to Houston is LEARN network. Preference would be direct connectivity. Space tight - 60 TB free. Perc6 card issue on new storage. Will soon bring in 200 TB of storage, estimate tomorrow.
    • this week: A problem with the 6248 switch stack. AGLT2 found a problem when switch stack module #7 was added (known firmware problem). Sometimes lose filesystem, or have bad flash - sometimes updates fail. Shawn notes problems with version 3 of the firmware.

  • SWT2 (OU):
    • last week: Ready to bring OU back online. Waiting to be added to ToA, then ready for testing. Almost there - few issues with ATLAS release location, in contact with Mark; suggests cc'ing Alden in reply.
    • this week: Ready for test jobs, Mark will send some this afternoon.

  • WT2:
    • last week(s): Ordering next storage - consulting w/ Shawn very helpful. Decided to go with Dell even if low-density. 15 R610 (to save a little space), 45 MD1000. 48GB memory. Running out of space. Deletion is going on but slowly (small files perhaps)?
    • this week: Working on a storage configuration from Dell. 7 R710s each with 6 MD1000s. Two 8024F switches, a 10G switch - a new offering from Dell.

Carryover issues ( any updates?)

Conditions data access from Tier 2, Tier 3 (Fred, John DeStefano)

  • Reference
  • last week(s)
    • Instructions for installing Squid start here - SquidTier2
    • Updates to SiteCertificationP13 upon completion
    • Notification to Fred for testing
    • Notification to John for completion, and update of the https://twiki.cern.ch/twiki/bin/view/Atlas/T2SquidDeployment deployment page
    • Problems with sites not failing over to the secondary Squid lauchpads?
    • Fred will test actual failover for a DNS round-robin server for Squid at AGLT2.
    • Tier 3's will need backup - associate with a Tier 2
    • Monitor the squid; Cacti monitoring, Monit monitoring; Nagios plugin (general, or squid-frontier); is there anything for Ganglia.
    • Fred testing SLAC. AGLT2 tests worked -
    • John: fail-over policy; if squid fails, it would try another T2 site. Not working. Discussing new policy to fail over to Frontier server at cloud's T1; if fails there then it tries CERN; if fails there it fails the job. Seeing silent fail-overs to Oracle database.
    • Its not understood how the configuration for the failover choice is determined.
    • Fred will investigate further
  • this week
    • Fred has tested squids everywhere except NET2 where firewall issues are being worked out.
    • OU still needs setup and testing
    • Local setup files from each Tier 2 are being compared against ToA
    • Fail-overs should work, but Wei notes there may be a firewall issue failing over WT2 to SWT2.
    • Problem at BNL launch-pad due to tomcat/java issue
    • Fred will review configuration files eveywhere

Release installation, validation (Xin)

The issue of validating process, completeness of releases on sites, etc.
  • last meeting
    • BNL available for testing. OU will also be available soon. Will keep bugging Alessandro.
  • this meeting:
    • Testing underway at OU and UTD, seems successful
    • Migration should be transparent to production: new installation will have different directory structure, will provide sym-links for compatibility
    • Will do this one site at a time, starting with BNL
    • Will start with the next release/cache.

AOB

  • last week
  • this week


-- RobertGardner - 15 Jun 2010

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