Changes between Initial Version and Version 1 of tier-one-meeting-20190129


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Timestamp:
01/29/19 15:02:08 (23 months ago)
Author:
paul
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  • tier-one-meeting-20190129

    v1 v1  
     1[[TOC(depth=0)]] 
     2= dCache Tier I meeting January 29, 2019 = 
     3[part of a [wiki:developers-meetings series of meetings]] 
     4 
     5== Present == 
     6 
     7dCache.org(Paul), IN2P3(), Sara(), Triumf(), BNL(), NDGF(Jens), PIC(), KIT(Samuel), Fermi(), CERN() 
     8 
     9= Agenda = 
     10 
     11(see box on the other side) 
     12 
     13= Site reports = 
     14 
     15== NDGF == 
     16 
     17Things going as expected. 
     18 
     19=== WebDAV door performance issues === 
     20 
     21issue -- fall-out webdav door problem. 
     22 
     23Narrowed it down to two causes 
     24 
     25Problem #1: the door in use was a non-redirecting door.  This proxied all the transfers.  With a distributed setup, this hurts badly. 
     26 
     27See approximately 10x performance boost from redirected. 
     28 
     29Problem #2: arccp for doing the copies.  As it turns out, they use byte-ranges. 
     30 
     31URL option to disable this "feature".  Disabling this gives ~5x improvement boost. 
     32 
     33The new version, arc v6, will have this disabled by default. 
     34 
     35Also tried this with the gfal-copy command. 
     36 
     37With non-partial GET, gfal-copy and arccp are about  
     38 
     39467 MiB/s 
     40 
     41arccp partial GETs, non-redirecting door 4 MiB/s 
     42 
     43== KIT == 
     44 
     45Everything is running fine. 
     46 
     47=== SRM space accounting discrepancy === 
     48 
     49Talking about bug report by ATLAS, where rucio and SRM give different space usage.  Discrepancy was due to a bug in Rucio. 
     50 
     51=== Unreliable transfers with China === 
     52 
     53Transfers failing between China for GridFTP. 
     54 
     55Big files ~25 GiB files 
     56 
     57The onWrite option was 'on', now switched 'off'. 
     58 
     59=== SSH admin interface === 
     60 
     61Reminder: RT 9418 
     62 
     63= Support tickets for discussion = 
     64 
     65[Items are added here automagically] 
     66 
     67= DTNM = 
     68 
     69Same time, next week.