2022-06-01 Meeting notes
- Alastair Dewhurst
Date
Jun 1, 2022
Participants
@Alastair Dewhurst @Thomas, Jyothish (STFC,RAL,SC) @Thomas Byrne
From Lancaster Gerard Hand and Steven Simpson
Goals
To Discuss current XRootD issues and the development work to fix them.
Discussion topics
Item | Presenter | Notes |
|---|---|---|
| Waiting on Mark Slater. | |
Jyothish | The fix appears to be working >99.9% of the time. This needs to be rolled out to all external gateways. This will be done next week. The WN gateways already have this fix in place. Jyothish should add more detail to the ticket. | |
Jyothish | Lockless reads are on 50% of the 2017 generation. A detailed kibana page is showing how the performance differs. There is a lot of noise so we can’t really measure any improvement however it does provide reassurance that we can roll the change out across the farm. While the lockless read does not repeatedly lock the file, it is still stating and unlocking the file for every vector read. It would be quite complex to remove the stat command as it is sensible to do this for each rados object in the read, however it should be quite simple to remove the unlock from every sub read. |
Lancaster
XRootD servers are up and running. CephFS is fine. James Walder has made an update to the Rucio code to help with POSIX access. Waiting for testing to start.
Glasgow
Sam is currently running XRootD 5.4.3_rc3. XRootD was repeatedly crashing and dumping their cores, causing directories to fill up. Started midnight between Monday / Tuesday.