Cdms workshop

Notes for the CDMS workshop March 2014

MIDAS general picture

MIDAS main data path

hardware -> mfe user thread -> ring buffer ->
(compression thread -> ring buffer ->)
mfe main thread -> TCP socket ->
mserver -> event buffer -> event builder thread -> SYSTEM buffer -> 
mlogger -> (ring buffer -> compression thread -> ) data file -> 
lazylogger -> dcache/castor/hadoop/cloud storage

Needs to scale from 0.5GB/0.3GHz/1core PPC on FPGA to 1GB/1GHz/1core 32-bit ARM to 64GB/4GHz/12core 64-bit x86!

MIDAS web security

MIDAS slow controls paths

MIDAS history paths

Write path:

hardware ->
mfe -> SYSTEM buffer -> mlogger -> data.mid.gz
mfe -> ODB -> hotlink
mlogger -> hs_write -> .hst binary file, MySQL database, SQLITE database, (maybe "no sql" database)

Plot path:

user web browser ->
mhttpd -> hs_read -> read from .hst binary file, MySQL database, etc
-> use "gd" to make .png image -> send png file to user
-> (future: return to user a JSON data, plot using JS graphics)