Showing posts with label jamboree. Show all posts
Showing posts with label jamboree. Show all posts

27 September 2011

SRM speedup update

Or should that be speedupdate? If you remember the Jamboree last year, in Amsterdam, one of the suggestions to decrease the negotiation overheads in SRM by making more efficient use of the socket. Our very own Paul Millar from DESY has come up with a demonstrator using a lua shell which is able to reach SRMs by calling the functions in the API, like S2 does, but with perhaps a simpler language to learn, and you're in a shell.

What Paul demonstrated was the speedup associated with calling each function individually, and then by turning off GSI delegation, and finally by reusing the socket using HTTP KeepAlive. You'd not be surprised to see a big improvement - but of course the server must support KeepAlive.

Combined with the immediate return on srmGet when a file does not need staging, this could again speed up multiple file accesses (and of course you can still submit multiple file requests in a single SRM request.)

Paul has published the code, you can find the dCache LUA SRM interface.on the dCache web site.

17 June 2010

Have you heard this one before...

Sunny Amsterdam. Narrow streets, canals. Friendly locals, and a bicycle with your name on in it. Wonderful place for a WLCG data management jamboree.

The super brief summary of yesterday is that some people are pushing for a more network centric data model. They point to video streaming, although others point out that video streaming is very different from HEP analysis. (More in the next couple of GridPP storage meetings.)

Today is more on technology, some known, some less so. One particular piece I would like to highlight is NFS4.1 which is still progressing and is now said to be "wonderful." :-)

There are lots of discussions which sound oddly familiar. For example, use of P2P networks have been suggested before (by Owen, back in EDG) and it's now coming up again. But of course technology moves on and middleware matures, so revisiting the questions and the proposed solutions will hopefully be useful.

Oh, and Happy to J "birthday" T.