Technical Coordination Weekly
Zoom
ARC technical coordination group members and invited persons
14 April 2026,14:00 - 15:00
Present: Maikem, Ievgen, Balazs, Aleksandr, Anders (after 14:25), Oxana
News
Datadelivery on LUMI login node works better than SSHFS, no overloads observed.
A new development meeting dedicated to data staging jobs is proposed, probably digital. A physical meeting is possible in Fall.
Better handling of CAs
A request from Dune for a more flexible configuration is discussed (based on a private e-mail thread). A Bugzilla feature request will be created to collect the information and suggested solutions. Would require a new configuration block, so backwards-incompatible. Focus on the first part (option to configure separate CA distributions for client and server verifications), the complete disabling of X509 proxy would come later.
The OoM issue related to loading CA bundles into memory for each connection and not being unloaded is not easily solved, it seems to be an OpenSSL feature (~660 kb for ~390 CAs). If the keys are extracted, the problem is gone. The proposed fix breaks the behavior, so perhaps should only become default in ARC8, while for ARC7 it should be configurable (optional). Another feature request in Bugzilla will be opened (memory protection against large CA bundles).
Keeping CRLs updated is out of scope for ARC.
Bugs
The mismatching scope issue is probably already reported in Bugzilla, needs cross-checking.
AOB
REST interface and queue states need to be discussed.