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ID Date Author Topicup Subject
  1399   25 Sep 2018 Stefan RittSuggestionSelf-resetting alarm class
> If you run an external script anyway, you can also call "odbedit -c alarm" to
> reset all alarms. Or you could try to set the "Triggered" entry of that certain
> alarm to 0 (again, with odbedit), that could also work.

That would not really help, because you cannot trigger a script AFTER an alarm occurred. Having 
"self-resetting" alarms is actually not a bad idea. I could add a flag "Auto reset" which is false by 
default and can be set to true for this functionality. Will keep that in mind for the next 
development cycle.

Stefan
  1400   25 Sep 2018 Stefan RittSuggestionSelf-resetting alarm class
> I was planning to use the alarm system to display an information banner when a
> certain valve is open, but I would like it to go away again when the valve is
> closed.
> Is there a way to achieve that? Maybe reset the alarm from an alarm script?
> (Seems like a hack...)
> Maybe this could be a useful feature, to be able to define an alarm class that
> resets itself once the condition is no longer met?

Actually you can implement such a thing already now pretty quickly using custom javascript on 
the status page. Just read the valve state regularly from the ODB and dynamically modify the 
status page to show or hide a banner. Look how custom pages work in midas and try to apply 
this to the status page status.html which you find in the resources directory.

Stefan
  1422   26 Dec 2018 Konstantin OlchanskiSuggestionSelf-resetting alarm class
> > If you run an external script anyway, you can also call "odbedit -c alarm" to
> > reset all alarms. Or you could try to set the "Triggered" entry of that certain
> > alarm to 0 (again, with odbedit), that could also work.
> 
> That would not really help, because you cannot trigger a script AFTER an alarm occurred. Having 
> "self-resetting" alarms is actually not a bad idea. I could add a flag "Auto reset" which is false by 
> default and can be set to true for this functionality. Will keep that in mind for the next 
> development cycle.
> 

I second, this is a good idea. Sometimes I want "sticky" alarms that stay on to indicate that a bad thing happened in the 
past, sometimes I want self-resetting alarms that go away when a bad thing turns back into a good thing.

When I do this in a frontend, I manually trigger the alarm and manually clear the alarm, i.e. you can see this
done in ~addaq/online/src/fectrl.cxx

Use al_trigger_alarm() and al_reset_alarm().

This can also be done through the json-rpc interface - both calls are available as rpc commands - and so easy to use 
from javascript. (but there is no simple unix command line tool to issue json-rpc requests. ouch. must write one now.)

K.O.
  1441   24 Jan 2019 Andreas SuterSuggestionjson rpc API for history data
For us it would be a handy feature if history data could be requested directly
from a custom page (time range or run based intervals) . Here I am not talking
about history plots but I am talking about recorded time series data. This way
we could easily generate useful graphs. For instance, if we measure the voltage
(constant current) while cooling, we could instantly get the resistance versus
temperature. Often we would like to 'correlate' recorded slow control data.

Is it already possible to extract history data the way suggested?
  1443   24 Jan 2019 Konstantin OlchanskiSuggestionjson rpc API for history data
> For us it would be a handy feature if history data could be requested directly
> from a custom page (time range or run based intervals) . Here I am not talking
> about history plots but I am talking about recorded time series data. This way
> we could easily generate useful graphs. For instance, if we measure the voltage
> (constant current) while cooling, we could instantly get the resistance versus
> temperature. Often we would like to 'correlate' recorded slow control data.
> 
> Is it already possible to extract history data the way suggested?

There are sundry hs_read() json rpc methods already implemented in preparation
of writing a javascript based history viewer (did not happen yet).

You can try to use them, they should work, but have not been tested extensively.

To find this stuff:
a) go to the mhttpd "help" page, open the "json rpc schema in text table format", look for the "hs_xxx" methods.
b) also from the "help" page, open "javascript examples- example.html", scroll down to "hs_get_active_events". Press the buttons, they should 
work, look at the source code to see how to call the rpc methods from your own page.

K.O.
  1536   29 May 2019 Suzannah DavielSuggestionReplacing MIDAS status page with custom status page
Replacing the MIDAS status page with a custom status page documented at

https://midas.triumf.ca/MidasWiki/index.php/Custom_Page_Features#Replace_Status_Page_by_a_Custom_page

does not appear to be supported in the current MIDAS version. 

As two of my experiments use this feature may I suggest its reinstatement?

Suzannah
  1537   31 May 2019 Stefan RittSuggestionReplacing MIDAS status page with custom status page
> Replacing the MIDAS status page with a custom status page documented at
> 
> https://midas.triumf.ca/MidasWiki/index.php/Custom_Page_Features#Replace_Status_Page_by_a_Custom_page
> 
> does not appear to be supported in the current MIDAS version. 
> 
> As two of my experiments use this feature may I suggest its reinstatement?

It still works, but is actually simpler. The status page is now a "dynamic" page, meaning mhttpd just servers an html file to 
the browser and everything is done in JavaScript there. The file for the status page is under midas/resources/status.html. 
You can easily change that file or replace it with a completely different (custom) file without having to change the ODB. 

There is only one potential problem. All midas html pages now have a certain structure, as written in 

https://midas.triumf.ca/MidasWiki/index.php/Custom_Page#How_to_use_the_standard_MIDAS_navigation_bars_on_your_cust
om_page

So if you have an existing custom status page, you might have to change it slightly to include the standard elements 
"mheader" and "msidenav". But this allows you to have the standard menu on your custom page and alerts displayed at the 
top row of your custom page (which was not possible before).

Once this works for you, it would be nice to adjust the documentation to reflect this new way.

Stefan
  1584   02 Jul 2019 Lukas GerritzenSuggestionmy_global.h not present in my linux distribution (needed)
Hey,

while trying to compile Midas under openSUSE 15.0 with mysql support, I was
running into the problem that somehow the mysql header file my_global.h is not
included in the packages. This might be a bug that concerns the suse developers
more, but is it actually needed? Compilation worked fine with the include line
commented out.

If it's not needed, I would like to suggest to remove line 735 of
src/history_schema.cxx (where it's included)

Cheers
Lukas

mysql  Ver 15.1 Distrib 10.2.22-MariaDB, for Linux (x86_64) using  EditLine wrapper
Also, all mariadb development packages are installed
  1585   02 Jul 2019 Konstantin OlchanskiSuggestionmy_global.h not present in my linux distribution (needed)
Confirmed. my_global.h is removed in MySQL 8.0 (gives a compile error) and deprecated in 
MariaDB 10.2 (gives a #warning).

I removed include of my_global.h, it is not needed on el6, el7 and ubuntu.

Also added explicit support for mariadb via mariadb_config if it exists.

Note that the cmake build does not actually enable mysql, sqlite and odbc - it detects them, but 
does not do anything about it. We will fix this shortly.

K.O.




> Hey,
> 
> while trying to compile Midas under openSUSE 15.0 with mysql support, I was
> running into the problem that somehow the mysql header file my_global.h is not
> included in the packages. This might be a bug that concerns the suse developers
> more, but is it actually needed? Compilation worked fine with the include line
> commented out.
> 
> If it's not needed, I would like to suggest to remove line 735 of
> src/history_schema.cxx (where it's included)
> 
> Cheers
> Lukas
> 
> mysql  Ver 15.1 Distrib 10.2.22-MariaDB, for Linux (x86_64) using  EditLine wrapper
> Also, all mariadb development packages are installed
  1586   03 Jul 2019 Lukas GerritzenSuggestionmy_global.h not present in my linux distribution (needed)
Thanks!
  1647   07 Aug 2019 Pintaudi GiorgioSuggestionROOT and multi-threading
Hello!
I am creating this thread to comment on an issue raised today during the MIDAS 
workshop.

It was said that ROOT doesn't play well with multithreading ... and it is 
definitely true. But since last year, many improvements have been done in ROOT 
multi-threading support and now even the ROOT fitter can be made thread-safe.

I know this because recently I had to completely rewrite the calibration 
software for the WAGASCI experiment and I wanted to use many ROOT analyzers in 
parallel.

Getting ROOT to work in a multi-thread environment is not painless. It took me 
many weeks to get to the end of it. But if using the latest ROOT version (from 
about ROOT 6.12.00 onwards), it should be possible. Basically, you have to 
compile ROOT with the Minuit2 minimizer support and then select it.

This is the thread on the ROOT forum where I have asked about and solved my 
issues (I am LastStarDust): https://root-forum.cern.ch/t/root-crashes-in-multi-
threaded-environment/35407

You can also refer to this bug report: https://sft.its.cern.ch/jira/browse/ROOT-
7173
and this documentation page: https://root.cern.ch/how/how-express-parallelism-
many-cores

Hope it may help.
Giorgio
  1651   08 Aug 2019 Art OlinSuggestionmidas cmake migration
I want to report a bug in the ROOT build process that might be relevant to the midas implementation. I had an annoying failure to build root 6.18 (current pro version) with a misleading error message about a fault in the root code. It turned out this was a cmake problem, and the error was from my cmake version being older than 3.14, which is quite recent. Took a bit of searching to find this.

I recommend when the cmake version is distributed that the instructions include the required cmake version. Developers are generally working well ahead of what is available in the older OS's.
  1652   08 Aug 2019 Stefan RittSuggestionmidas cmake migration
Each CMakeLists.txt should specify which version of CMake it requires. The MIDAS CMakeLists.txt requires CMake 3.1 or later. 
We deliberately stayed away from fancy cutting edge CMake features in order to make midas easier to compile. On top of that,
midas is a much simpler package compared to root, so things are not so complicated.

Stefan
  1653   08 Aug 2019 Konstantin OlchanskiSuggestionmidas cmake migration
> Each CMakeLists.txt should specify which version of CMake it requires. The MIDAS CMakeLists.txt requires CMake 3.1 or later. 
> We deliberately stayed away from fancy cutting edge CMake features in order to make midas easier to compile. On top of that,
> midas is a much simpler package compared to root, so things are not so complicated.

The oldest cmake I actually used is 3.6.1 (on SL6), so I do not know if cmake versions between 3.1 and 3.6 actually work for us. Perhaps we should set 
the CMakefile requirement to 3.6.1 to match the oldest version we know works. If somebody has an older cmake, they have a choice of updating it or 
trying it as as and reporting success/failure to the midas forum here.

K.O.
  1655   08 Aug 2019 Stefan RittSuggestionmidas cmake migration
I just tried CMake 3.1.0 and it worked with midas. So I believe all versions between 3.1.0 and 3.6.1 are ok.

Actually playing around with different versions I realized that 3.0.0 is also ok, so I changed the requirement of midas down to 3.0

Stefan
  1701   23 Sep 2019 Frederik WautersSuggestionrecover daq and hardware safety.

We have encountered a safety issue with our HPGe HV and it's midas frontend. Turning off or changing HV unknowingly has to be avoided at all costs.

 

Current safety protection

We use the DF_REPORT_STATUS flag to give the hardware settings precedence over odb settings. This all takes place in the init.

 

DAQ recovery Issue?

In the setup / development state, we sometimes have to remove the SHM files and reload an odb dump to recover the DAQ. When the FE is running, this can modify hardware settings. E.g. change a voltage

 

Question

Is there a way one can let the frontend know the "load"  function is called in odbedit? Or other suggestions to build in this safety.

 

  1708   27 Sep 2019 Konstantin OlchanskiSuggestionrecover daq and hardware safety.
> We have encountered a safety issue with our HPGe HV and it's midas frontend.

At TRIUMF and other labs the words "safety issue" have very specific meaning and
we tend to follow this guidance: MIDAS is not certified for and is not intended for use with 
safety critical applications as defined here:
https://en.wikipedia.org/wiki/Safety-critical_system

> A safety-critical system ... malfunction may result in ... following outcomes:
> death or serious injury to people
> loss or severe damage to equipment/property
> environmental harm

If this is your case, you should use properly certified software *and hardware*. Safety 
officers at most institutions require certified hardware interlocks and other protections to 
prevent such undesirable outcomes. Use of certified PLCs is sometimes permitted.

But I suspect in your case, there is no "safety issue", you only want to protect some 
valuable but not critical equipment against accidental damage.

In this case, you can probably use midas, but if midas malfunction may result in destroying 
your experiment (i.e. accidentally set wrong voltage on 3000 phototubes), you should also 
have hardware based protections (hardware limits on max/min high voltage). Most HV 
power supplies implement such protections (screw-driver actuated max voltage limits).

If there is danger of destroying your experiment you should also have an independent 
review of your control system to avoid avoidable mistakes and obvious problems.

> Turning off or changing HV unknowingly has to be avoided at all costs

The function of changing high-voltage is implemented in your frontend program. Right in 
the place in this program where you transmit the voltage setting from ODB to the hardware 
is where you implement your protections (validate the voltage range, check that changing 
the voltage is permitted, etc). This protects you against unexpected/incorrect/erroneous
changes in ODB (wrong ODB is loaded, wrong values in ODB, ODB is corrupted, etc).

In addition, it is wise to set software based limits in the HV power supply (software 
controlled max high voltage, software controlled max current, etc). Most HV power supplies 
implement such functions.

To ensure high voltage cannot be changed at the wrong times, you can also implement 
procedural and hardware protections, such as unplug the power supply control connection 
(usually ethernet or serial or usb cable). This will prevent you from monitoring the high 
voltage currents and the only solution is to use a  power supply with a hardware "write 
protect" function (a key needs to be inserted and turned to allow changing anything).

All of this is generic and applies to any controls software, not just MIDAS.

Without at least some of these protections (especially protections in your frontend 
program), the questions you asked about loading ODB are insufficient.

K.O.
  1712   28 Sep 2019 Frederik WautersSuggestionrecover daq and hardware safety.
Dear Konstantin,

So let me retract the term "safety issue" then, it was more a request/question for this type of 
info between the fe and the odb.

We have most of what you mention:
* The HV hardware has current limits
* The Hardware has fixed ramping limits.

same for the software. 

The issue occurs when e.g. one channel can not be turned on and ramp for some temp/specific 
reason, and someone else is working on the daq and reloads the odb for e.g. 1h ago.  

> > We have encountered a safety issue with our HPGe HV and it's midas frontend.
> 
> At TRIUMF and other labs the words "safety issue" have very specific meaning and
> we tend to follow this guidance: MIDAS is not certified for and is not intended for use with 
> safety critical applications as defined here:
> https://en.wikipedia.org/wiki/Safety-critical_system
> 
> > A safety-critical system ... malfunction may result in ... following outcomes:
> > death or serious injury to people
> > loss or severe damage to equipment/property
> > environmental harm
> 
> If this is your case, you should use properly certified software *and hardware*. Safety 
> officers at most institutions require certified hardware interlocks and other protections to 
> prevent such undesirable outcomes. Use of certified PLCs is sometimes permitted.
> 
> But I suspect in your case, there is no "safety issue", you only want to protect some 
> valuable but not critical equipment against accidental damage.
> 
> In this case, you can probably use midas, but if midas malfunction may result in destroying 
> your experiment (i.e. accidentally set wrong voltage on 3000 phototubes), you should also 
> have hardware based protections (hardware limits on max/min high voltage). Most HV 
> power supplies implement such protections (screw-driver actuated max voltage limits).
> 
> If there is danger of destroying your experiment you should also have an independent 
> review of your control system to avoid avoidable mistakes and obvious problems.
> 
> > Turning off or changing HV unknowingly has to be avoided at all costs
> 
> The function of changing high-voltage is implemented in your frontend program. Right in 
> the place in this program where you transmit the voltage setting from ODB to the hardware 
> is where you implement your protections (validate the voltage range, check that changing 
> the voltage is permitted, etc). This protects you against unexpected/incorrect/erroneous
> changes in ODB (wrong ODB is loaded, wrong values in ODB, ODB is corrupted, etc).
> 
> In addition, it is wise to set software based limits in the HV power supply (software 
> controlled max high voltage, software controlled max current, etc). Most HV power supplies 
> implement such functions.
> 
> To ensure high voltage cannot be changed at the wrong times, you can also implement 
> procedural and hardware protections, such as unplug the power supply control connection 
> (usually ethernet or serial or usb cable). This will prevent you from monitoring the high 
> voltage currents and the only solution is to use a  power supply with a hardware "write 
> protect" function (a key needs to be inserted and turned to allow changing anything).
> 
> All of this is generic and applies to any controls software, not just MIDAS.
> 
> Without at least some of these protections (especially protections in your frontend 
> program), the questions you asked about loading ODB are insufficient.
> 
> K.O.
  1715   29 Sep 2019 Konstantin OlchanskiSuggestionrecover daq and hardware safety.
> 
> The issue occurs when e.g. one channel can not be turned on and ramp for some temp/specific 
> reason, and someone else is working on the daq and reloads the odb for e.g. 1h ago.  
> 

So you want to ensure that some HV channels are turned off and stay turned off. Yes?

Most effective solution will depend on the consequences of unwanted turning-on of your channels:

- if hardware is destroyed if turned on - I think you should have a hardware lock-out. (unplug the HV cable)
- if hardware malfunctions and will degrade if left turned on for long time (i.e. a hot phototube or sparking wire chamber) - your data 
monitoring software should detect the anomaly (it will show up as a hot channel, dead channel, etc) and the people running the 
experiment will realize the mistake and turn the channel back off. also hardware monitoring (HV currents, etc) should detect this, with 
same effect.
- if collected data becomes useless (the turned-off channel make big noise in all other channels), then same thing, your data 
monitoring should catch it.

The next consideration is what are you protecting against:

a) one person flags channel defective, turns it off, next person knows nothing, turns it back on - you need to work on documentation, 
shift hand-off and other human-level procedures
b) people running experiment load random odb files - same thing, from human-level procedures and documentation it should be made 
clear which odb files are correct and which should not be used
c) software malfunction (not human person) causes data change in odb causes turned-off channel to turn back on
d) hardware malfunction causes turned-off channel to turn back on (HV power supply hardware or firmware malfunctions and decides 
that all channels should be turned on at maximum high voltage)

In the experiments I am most familiar with, problem (b) is avoided by never loading/reloading odb files directly, most/all interaction
with the experiment is done through web pages, and these web pages are carefully coded to be safe against most user mistakes.

Cases (a), (b) and (c) you can protect against by changing the frontend code to refuse to turn on some channels:

int set_hv(int channel, int voltage) {
   if (channel == 35) return COMMAND_REFUSED;
   write_to_hardware(channel, voltage);
   return COMMAND_SUCCESS;
}

But in reality this solution only creates problem (e):

e) people running the experiment start random versions of the frontend program, make random changes to the frontend source code, 
multiple people working on the frontend have their own personal versions/copies of the source code, etc.

This is the worst-case scenario, meaning the experiment lost control of software configuration, and even basic software version 
control tools (like svn or git) are not being used. If your experiment gets that chaotic, all protections are likely to be ineffective - 
documentation will not work (people will ignore post-it notes "do not turn on!"), hardware protections will not work (unplugged cable 
labeled "do not plug in!" will be plugged back in and powered), etc. good luck, then.

K.O.
  1726   15 Oct 2019 Stefan RittSuggestionrecover daq and hardware safety.
There is a not-so-well-known function in the ODB to write protect some keys. You can do

odbedit> chmod 1 /Equipment/HV/Demand

which will write protect your Demand values. You see that by doing

odbedit> ls -ls

where you only see a "R" at the right end instead a "RWD". I haven't tried it yet (so better do a dry run yourself), but that should prevent an odb load to overwrite your demand values. To change the values, put some logic on a custom page to unprotect the 
values, change them, and then protect them again.

Stefan
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