Difference between revisions of "35t DAQ"
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(Created page with "= Recent documents = * [http://lbne2-docdb.fnal.gov:8080/cgi-bin/ShowDocument?docid=9677 DocDB 9677, Proposed Run Modes for the 35t test] * [http://lbne2-docdb.fnal.gov:8080/...") |
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* how does this "chunk" correspond to a trigger for each expected trigger criteria? | * how does this "chunk" correspond to a trigger for each expected trigger criteria? | ||
* what time-ordering is expected from data coming out of the DAQ, particularly between disparate sources (e.g. Wires/PDs)? | * what time-ordering is expected from data coming out of the DAQ, particularly between disparate sources (e.g. Wires/PDs)? | ||
| + | * are we going to implement a "world clock" with 1 us resolution? | ||
* what unit of data "chunk" ("event") is required and desired for offline analysis? | * what unit of data "chunk" ("event") is required and desired for offline analysis? | ||
* what offline analysis decisions/limitations can we, as a collaboration, be comfortable "baking in" to this choice of unit? | * what offline analysis decisions/limitations can we, as a collaboration, be comfortable "baking in" to this choice of unit? | ||
* how are DAQ data "chunks" (triggers) numbered? How are offline data "chunks" ("events") numbered? | * how are DAQ data "chunks" (triggers) numbered? How are offline data "chunks" ("events") numbered? | ||
* what is the mapping from the former to the latter? | * what is the mapping from the former to the latter? | ||
| − | * what changes to art and/or | + | * what changes to ''art'' and/or LArSoft are needed to accommodate the above answers? |
Revision as of 15:26, 17 October 2014
Recent documents
- DocDB 9677, Proposed Run Modes for the 35t test
- DocDB 9785, Report from RCE-Backend Mini-workshop
- DocDB 9591, 35t Phase-II Testing for August Readiness Review
- DocDB 9823, summary for plans in mid-Fall 2014
Run Modes (per DocDB 9677)
| No. | Mode | Description | Comment |
|---|---|---|---|
| 1 | Continuous main DAQ mode | Similar to final 'triggerless' far detector running mode, i.e. parallel trigger farm looks for nice muons in real time. Needs ZS of TPC data to work. | --- |
| 2 | Triggered main DAQ mode | Main selection is external trigger counter | --- |
| 3 | Immediate triggered mode | Use TOC triggered mode (only outputs data in window) or SSP triggered mode to avoid bottleneck. | This is a fallback option of there is bottleneck in either RCE or SSP data. |
| 4 | Triggered window mode | TPC in triggered non-zero suppressed mode | Use before we are happy with ZS in RC |
| 5 | Wide-window burst mode | TPC in burst mode with the longest window possible (512MB buffer = 0.5s). | Special run mode for offline ZS studies |
| 6 | Burst mode | Collect data in certain time window (could either determine this from a Nova time hash function, or using Penn board trigger input | Fallback before ZS works in RCE, this is also the mode for measuring noise, i.e. this is the mode for November vertical slice test |
Issues
- Purposes and architecture of the proposed online farm
- Design of the metadata
- Handling TPC stream data within the framework which is trigger-oriented, issues of timing and multiple interaction in temporally close slices
- Possible necessity to duplicate parts of raw data to create overlaps, in order to make practical operation of the online farm
Misc Questions
In no particular order, these are the questions pertaining to DAQ and its interface with off-line:
- what is the low level DAQ file format/encoding (ROOT? binary?)
- what schema does the content of DAQ files follow?
- where is a diagram showing all the parts of the DAQ data stream with their names (millislice, microblock, tick, "trigger", etc)?
- what is the start/stop criteria that defines the highest level "chunk" of data (e.g. a "trigger")?
- how does this "chunk" correspond to a trigger for each expected trigger criteria?
- what time-ordering is expected from data coming out of the DAQ, particularly between disparate sources (e.g. Wires/PDs)?
- are we going to implement a "world clock" with 1 us resolution?
- what unit of data "chunk" ("event") is required and desired for offline analysis?
- what offline analysis decisions/limitations can we, as a collaboration, be comfortable "baking in" to this choice of unit?
- how are DAQ data "chunks" (triggers) numbered? How are offline data "chunks" ("events") numbered?
- what is the mapping from the former to the latter?
- what changes to art and/or LArSoft are needed to accommodate the above answers?
