1. BLM settings management in LSA
BLM Audit
10/06/2008
Grzegorz Kruk (AB-CO-AP)

2. BLM settings management
Agenda
LSA settings management basics
Parameter space for BLMs
Generation of initial BLM settings
Trims & sending settings to the HW
MCS for BLMs
Testing
Operational validity checks
Summary
10/06/2008
BLM settings management

3. BLM settings management
Agenda
LSA settings management basics
Parameter space for BLMs
Generation of initial BLM settings
Trims & sending settings to the HW
MCS for BLMs
Testing
Operational validity checks
Summary
10/06/2008
BLM settings management

4. Settings management basics Key Concepts
Parameter
Settable or measurable entity on a device (real or virtual) e.g. LHCBEAM/QPH, MPLH.41994/K, MPLH4199/IREF
In case of FESA – one parameter corresponds to one property field e.g. BPMOPOS_1/Setting#gain (<device>/<property>#<field>)
Context
Super Cycle
Cycle
Beam process (LHC)
Non-Multiplexed (context independent) – BLM thresholds case
Setting
Value of a parameter
for a given context
Context
Parameter
Setting
10/06/2008
BLM settings management

5. Settings management basics Parameter space
Parameters can be organized in hierarchies
Each hierarchy describes relations between parameters
Change of a parameter affects all its dependant parameters
Roots  usually physics parameters
e.g. momentum, tune, chromaticity,…
Leaves  hardware parameters
e.g. reference current on power converters
LSS4_EXT_BUMP/KNOB
MPLH /K
MPSH.42198/K
MPLH /I
MPSH.42198/I
MPLH4199/IREF
MPSH4219/IREF
10/06/2008
BLM settings management

6. Settings management basics LHC Horizontal Tune parameter space
10/06/2008
BLM settings management

7. Settings management basics Settings initialization
In order to manage settings we need to initialize them:
Using ValueGenerators
Compute initial setting based on optics
Typically defined for a parameter type e.g. LHCMomentumValueGenerator
By acquisition from hardware
This can be done at the moment only for parameters which directly correspond to device properties i.e. for parameters which represent FESA properties (fields)
10/06/2008
BLM settings management

8. Settings management basics Trim
10/06/2008
BLM settings management

9. BLM settings management
Agenda
LSA settings management basics
Parameter space for BLMs
Generation of initial BLM settings
Trims & sending settings to the HW
MCS for BLMs
Testing
Operational validity checks
Summary
10/06/2008
BLM settings management

10. Parameter space for BLMs
Threshold values for all energy levels and integration times
BLM family
Master table
Set up by BLM experts x
Factors [0 -> 1] for all monitors belonging to given family
Edited (trimmed) by operators
Monitor factors =
Sent to the hardware
Applied table
Product of the multiplication
10/06/2008
BLM settings management

11. Parameter space for BLMs
BLM family 1
BLM family N
Threshold values for all energy levels and integration times
Master table
Master table … x x
Factors [0 -> 1] for monitors belonging to given family
Monitor factors
Monitor factors = =
Product of the multiplication
Applied table
Applied table
Thresholds (72 fields)
- thresholdsCard1
- thresholdsCard2
- …
Applied tables must be combined into the format of the FESA property
Sent to the crate over CMW
BLM Crate
10/06/2008
BLM settings management

12. Parameter space for BLMs
Tables in LSA DB
Master table
BLM_INFO
BLM_FAMILIES
BLM_FAMILY_THRESHOLDS x
BLM_1 / MONITOR_FACTOR …
Monitor factors
Parent-child relation between all monitor factors and field parameters
BLM_256 / MONITOR_FACTOR =
CRATE_X / Thresholds# monitorThresholdCoefficients
CRATE_X / Thresholds# thresholdsCard1
Applied table
CRATE_X / Thresholds# thresholdsCard2
CRATE_X / Thresholds# …
LSA Parameters
10/06/2008
BLM settings management

13. BLM settings management
Agenda
LSA settings management basics
Parameter space for BLMs
Generation of initial BLM settings
Trims & sending settings to the HW
MCS for BLMs
Testing
Operational validity checks
Summary
10/06/2008
BLM settings management

14. Generation of initial BLM settings
Parameters representing Thresholds property fields (applied table) are not trimable
They are computed from monitor factors using a dedicated MakeRule
Values are kept in LSA DB as settings but they cannot be changed by LSA Trim API
What we generate are MONITOR_FACTOR parameters
Done with a dedicated ValueGenerator which initializes factor value with 1
10/06/2008
BLM settings management

15. Generation of initial BLM settings
10/06/2008
BLM settings management

16. BLM settings management
Agenda
LSA settings management basics
Parameter space for BLMs
Generation of initial BLM settings
Trims & sending settings to the HW
MCS for BLMs
Testing
Operational validity checks
Summary
10/06/2008
BLM settings management

17. Trim <uses> BLM_MakeRule Tables in LSA DB BLM_INFO BLM_FAMILIES
BLM_X / MONITOR_FACTOR
Tables in LSA DB
BLM_INFO
<uses>
BLM_MakeRule
BLM_FAMILIES
BLM_FAMILY_THRESHOLDS
CRATE_X / Thresholds# monitorThresholdCoefficients
CRATE_X / Thresholds# thresholdsCard1
CRATE_X / Thresholds# thresholdsCard2
CRATE_X / Thresholds# …
10/06/2008
BLM settings management

18. BLM settings management
Trim
10/06/2008
BLM settings management

19. BLM Threshold Factors Editor BLM settings management
Slides by Fabio Follin, AB/OP
10/06/2008
BLM settings management

20. BLM Threshold Factors Editor
Security assured by RBA and LSA Trim API
The BLM threshold factors are loaded from LSA
Possibility to load all monitors or load only the monitors of a family
Possibility to add a filter to the threshold factors loaded:
Location (Quad, …)
Type (IC, SEM)
Section (LSS, DS, ARC)
Sector Part (Left, Right)
Sector Number (1 to 8)
Beam (1 or 2)
Transverse position (External, Internal, Top, Bottom)
Position on Element (Entrance, Center, Exit)
Observed Element
Slides by Fabio Follin, AB/OP
10/06/2008
BLM settings management

21. BLM Threshold Factors Editor
Threshold factors can be displayed and edited in a graph or a table
Edition is like normal Trim Editor
Possibility to set, add or subtract an offset or multiply with a factor
The range of the threshold factors is from 0 to 1
The editor prevents to send values out of range
A Trim History management will be provided
The threshold factors modified are send to Hardware via the LSA Trim API
Slides by Fabio Follin, AB/OP
10/06/2008
BLM settings management

22. Sending settings to the HW
Every time a single or a group of monitor factors are modified – the corresponding applied table is sent to the crate
Setting the whole property for a one crate takes quite some time
We observed from 20s to over a minute
10/06/2008
BLM settings management

23. BLM settings management
Agenda
LSA settings management basics
Parameter space for BLMs
Generation of initial BLM settings
Trims & sending settings to the HW
MCS for BLMs
Testing
Operational validity checks
Summary
10/06/2008
BLM settings management

24. MCS for BLMs
Every time any monitor factor is modified  applied table together with digital signature are recomputed
BLM_1 / MONITOR_FACTOR …
BLM_256 / MONITOR_FACTOR
CRATE_X / Thresholds# monitorThresholdCoefficients
CRATE_X / Thresholds# thresholdsCard1
signature field is sent to the crate together with all other fields and verified on the front-end
CRATE_X / Thresholds# thresholdsCard2
CRATE_X / Thresholds# …
CRATE_X / Thresholds#signature
LSA
Front-end
MCS verification
BLM Crate
10/06/2008
BLM settings management

25. BLM settings management
Agenda
LSA settings management basics
Parameter space for BLMs
Generation of initial BLM settings
Trims & sending settings to the HW
MCS for BLMs
Testing
Operational validity checks
Summary
10/06/2008
BLM settings management

26. BLM settings management
Testing
Where can we possibly have a problem? (from LSA point of view)
Incorrect master table ?
Incorrect parameter space e.g. wrong hierarchy between monitor factors and corresponding crate fields
Validation of the hierarchy in the BLMMakeRule (on each trim)
Bugs in BLMMakeRule or in the code reading BLM info and master table
Unit testing (Junit)
Driving to the hardware can be buggy
Bugs on the front-end
Bugs in the hardware (e.g. in electronics)
10/06/2008
BLM settings management

27. BLM settings management
‘Read-back’ test
The master table and monitor factors where defined in DB with such values that the test code can deduce what should be the correct threshold value (what it should expect) e.g. threshold on card 1, channel 1, energy level 1 and running sum 1 should be 1111
Master table
Parameter space
DAO objects (finders, persisters
BLMMakeRule
Drive settings to HW
Test code
Send test thresholds to the tested crate
The test code doesn’t use any DAO or master table and it was written by a different person
Front-end
Hardware
10/06/2008
BLM settings management

28. BLM settings management
Testing
Where can we possibly have a problem? (from LSA point of view)
Incorrect master table ?
Incorrect parameter space e.g. wrong hierarchy between monitor factors and corresponding crate fields
Validation of the hierarchy in the BLMMakeRule (on each trim)
Bugs in BLMMakeRule or in the code reading BLM info and master table
Unit testing (Junit) + ‘Read-back’ test
Driving to the hardware can be buggy
Bugs on the front-end
‘Round Trip’ test
Errors in the hardware (e.g. in electronics)
The ‘Read-back’ test doesn’t ensure that there are no bugs, but significantly decreases the risk
10/06/2008
BLM settings management

29. BLM settings management
Agenda
LSA settings management basics
Parameter space for BLMs
Generation of initial BLM settings
Trims & sending settings to the HW
MCS for BLMs
Testing
Operational validity checks
Summary
10/06/2008
BLM settings management

30. Operational validity checks
The unit testing or ‘Round-trip’ test can be used when new software/hardware version is released, but what if piece of electronics breaks or somebody changes thresholds on the crate somehow bypassing LSA?
MCS check – functionality provided by LSA (exposed via an API)
Checks whether signature correspond to settings (it might be not true if somebody edits settings directly in DB tables) and compares settings stored in LSA DB with values on the front-end (whether they are equal)
Returns OK or NOT OK – plus some more detailed info if NOT OK
Can be executed by the LHC sequencer e.g. before each injection or periodically by SIS (Software Interlock System)
Such a functionality has been already requested by OP for other MCS devices
10/06/2008
BLM settings management

31. BLM settings management
Agenda
LSA settings management basics
Parameter space for BLMs
Generation of initial BLM settings
Trims & sending settings to the HW
MCS for BLMs
Testing
Operational validity checks
Summary
10/06/2008
BLM settings management

32. BLM settings management
Summary
We (LSA) are ready to manage BLM thresholds – BLMMakeRule, drive to HW, DAO have been implemented and tested
The whole mechanism hasn’t been used yet operationally –tested only by an LSA developer on one crate
We have unit tests for the make rule, drive and DAOs and we have also a set up for the ‘Read-back’ test
a bit provisional
If operators / BLM experts would like to use it – it should be set up more properly – e.g like MCS check or with some small dedicated GUI
Can we check correctness of the master table?
The thresholds editor is almost ready (by F.Follin)
The operational validity check (by LHC sequencer and SIS) could be implemented with not very big effort
by developers responsible for these products
Sending thresholds to the crate is a bit long
Might be annoying for operators
Not very comfortable for LSA itself (need to extend CMW timeout)
10/06/2008
BLM settings management

33. Questions?