NPPS Leadership Team

[Brett Viren <bv AT bnl.gov>]

Thanks Kolja,

I wonder if the S3 solution also provides the "read-ahead" feature that
makes XrootD so effective at latency hiding.

-Brett.

Kolja Kauder <kkauder AT gmail.com> writes:

> I _think_ Jerome essentially was just intrigued by the new and shiny S3 at 
> the beginning. Work on adding an
> XrootD layer did happen but stalled for reasons I'm not privy to and was 
> put "on pause" in July '22.
> Importantly, the following is an inference, not a thing I've actually 
> heard, but I strongly suspect that SDCC
> will point out that S3 has been working well for ECCE, ATHENA, and now 
> ePIC, so why divert resources from that?
>
> On Fri, Apr 28, 2023 at 8:44 AM Torre Wenaus via Phys-npps-mgmt-l 
> <phys-npps-mgmt-l AT lists.bnl.gov> wrote:
>
>     Thanks a lot Brett. Kolja is well versed in the (Jerome) arguments and 
> can comment.
>       Torre
>    
>     On Fri, Apr 28, 2023 at 8:42 AM Brett Viren <bv AT bnl.gov> wrote:
>    
>         Hi Torre,
>        
>         Mostly on XRootD:
>        
>         DUNE @ SDCC is small fry in comparison to EIC @ SDCC, both in 
> resource
>         needs and in that BNL is not the host, but XRootD and Rucio are 
> needed
>         in DUNE as well.  Maybe this "synergy" is somehow useful in your
>         arguments.
>        
>         I don't know the backstory but it seems really weird that XRootD is 
> a
>         sticking point.  At least I fail to see any effort/resource argument
>         against it.  Here's why:
>        
>         Back when LBNE (pre DUNE) and Daya Bay had RACF nodes, Ofer gave us
>         great service to set up and operate XRootD servers and clients.  
> These
>         groups were in the "free tier" of RACF service with only about a 
> dozen
>         nodes each.  I think the effort to scale from that to what EIC needs
>         would be rather less than linear in the number of nodes.  We also 
> had
>         the extra complication that the XRootD storage nodes doubled as 
> batch or
>         interactive nodes.  I expect keeping these roles separate would 
> make for
>         an even easier provision.  And adding that EIC is not in the "free 
> tier"
>         it seems historically inconsistent for the XRootD request to be 
> denied.
>
>         It may be useful to know the arguments from SDCC to refuse the 
> request.
>         Maybe they can be included in what you are assembling.
>
>         -Brett.
>        
>         Torre Wenaus via Phys-npps-mgmt-l <phys-npps-mgmt-l AT lists.bnl.gov>
>         writes:
>        
>         > Hi all,
>         > In addition to getting past the BNL embarrassment of not offering 
> XRootD to EIC despite years of
>         requests, I'd
>         > like to explore ways NPPS could help ePIC with a further and much 
> more impactful change in their data
>         > management, adopting Rucio. JLab is working on this now. At BNL 
> it sits (rightly) in the wings while
>         we focus
>         > on sPHENIX. If people have thoughts on how we can help, including 
> leveraging sPHENIX work without
>         impeding it,
>         > I'd like to hear them. 
>         >   Torre
>         >
>         > --
>         > -- Torre Wenaus, BNL NPPS Group, ATLAS Experiment
>         > -- BNL 510A 1-222 | 631-681-7892
>         > _______________________________________________
>         > Phys-npps-mgmt-l mailing list
>         > Phys-npps-mgmt-l AT lists.bnl.gov
>         > https://lists.bnl.gov/mailman/listinfo/phys-npps-mgmt-l
>
>     --
>     -- Torre Wenaus, BNL NPPS Group, ATLAS Experiment
>     -- BNL 510A 1-222 | 631-681-7892
>     _______________________________________________
>     Phys-npps-mgmt-l mailing list
>     Phys-npps-mgmt-l AT lists.bnl.gov
>     https://lists.bnl.gov/mailman/listinfo/phys-npps-mgmt-l
>
> --
> ________________________
> Kolja Kauder, Ph.D.
> NPPS, EIC
> Brookhaven National Lab, Upton, NY
> +1 (631) 344-5935
> he/him/his
> ________________________

Attachment: signature.asc
Description: PGP signature