Copy of 2023-04-13 Meeting Notes

Vector Read

https://stfc.atlassian.net/wiki/spaces/GRIDPP/pages/137265343/Non-striper+read+v+implementation+for+WN+s+xrootd+gateways

Code review largely complete; no additional meetings expected.
- Would like to resolve any residual comments, asap.

Planned actions:

• Complete the Code review, to allow:

  • Merge PR into master branch (and merge into bufferedIO)

• build rpms for 5.3.3 and 5.5.4 releases

• (supply Glasgow with appropriate tag / commits in GitHub to build their RPMS)

• Arrange testing on Echo prod, AAA and Alice gateways:

  • AAA testing with various buffer sizes would be interesting.

SEGV investigations with -S multi-stream flags

XRD-53 - Getting issue details... STATUS

The SEGV has not occured when using the Ceph plugin with XRootD v5.5.4.post257 (local compile). The reason for this is unknown; we have raised a query about this in https://github.com/xrootd/xrootd/issues/1821#issuecomment-1508126509

Fix for paged writes when misaligned to end of buffer

https://github.com/stfc/xrootd-ceph/pull/40

Sandbox on gw7; ready to be deployed?

CMSD status

XRD-41 - Getting issue details... STATUS

CC document

https://stfc.atlassian.net/wiki/spaces/GRIDPP/pages/136446019/High-level+XrootD+redirection+for+Echo?focusedCommentId=136118425

• Observed quick round-robin behaviour for ipv4; slow (according to TTL) for ipv6. James A. states this is fine; and different clients should get directed to different managers anyway.

• Failover behaviour appears to work (when manually stopping / xrootd or cmsd ). Best command for spotting a broken xrootd service ?

• AQ configuration exists, but should be refactored to add relevant “service” level functionality.

• ATLAS FTs running against it, and run some simple ‘stress’ test transfers; looking ok so far.

Todo;

• complete the AQ setup

• Deploy to all Echo gateways (still in the largely ‘passive’ mode).

• Define and agree an agenda / schedule, for moving VOs (and their various activities over).

  • Make final switch of webdav and echo aliases to the redirector address

  • This will need new certs for the two manager hosts

Transfers of 0-byte files

XRD-62 - Getting issue details... STATUS

Observed Dune transfer failures using 0-byte files